New features
This document describes the major changes occurring between versions of Modules. It provides an overview of the new features and changed behaviors that will be encountered when upgrading.
v5.4 (not yet released)
This new version is backward-compatible with previous version 5 release. It fixes bugs but also introduces new functionalities that are described in this section. See the 5.4 release notes for a complete list of the changes between Modules v5.3 and v5.4.
Purging sticky modules
The sticky_purge configuration option is added to define the
behavior of purge sub-command when unloading a sticky or
super-sticky module.
By default an error is raised. sticky_purge can be changed to
emit a warning message instead or to be silent.
$ module purge Unloading foo/1.0 ERROR: Unload of sticky module skipped $ module config sticky_purge warning $ module purge Unloading foo/1.0 WARNING: Unload of sticky module skipped $ module config sticky_purge silent $ module purge $ module list Currently Loaded Modulefiles: 1) foo/1.0 Key: sticky
Specific modulepath labels
modulepath-label command is introduced to define a label to use to
designate modulepath in module avail output. This new command should
be used in global or modulepath-specific rc files.
$ cat /path/to/modulefiles/.modulerc #%Module modulepath-label . Tools $ module avail foo ---------------------- Tools ---------------------- foo/1.0 foo/2.0
Unique module name loaded
The configuration option unique_name_loaded is introduced to allow
only one module loaded per module name. It is similar to the One name rule
feature introduced by the Lmod project.
When enabled, unique_name_loaded produces a conflict definition
at the start of modulefile evaluation for each actual and alternative module
root name. For instance when loading a module named foo/sub/1.0 with a
qux/1.0 alias, it produces a conflict against foo and qux.
When loading a module that shares a name with an already loaded module, an error is raised due to the conflict definition. This error aborts the module load evaluation.
$ cat /path/to/modulefiles/bar/1.0 #%Module $ cat /path/to/modulefiles/bar/2.0 #%Module $ module config unique_name_loaded 1 $ module load bar/1.0 $ module load bar/2.0 Loading bar/2.0 ERROR: Module cannot be loaded due to a conflict. HINT: Might try "module unload bar" first.
unique_name_loaded is disabled by default. It can be changed with
module config sub-command or at installation time with
--enable-unique-name-loaded configure script option.
Cache sourced files
You may have gathered common Tcl code files used by all your modulefiles in Tcl files that are sourced with source(n) Tcl command. When loading multiple modulefiles at once, these sourced files may be read for every loaded modules, which may induce some I/O load.
The configuration option source_cache is introduced to cache files
evaluated through source Tcl command in order to only read them once
during a modulecmd.tcl execution. When this option is enabled, sourced
file read also benefits from optimized I/O calls of Modules Tcl extension
library.
In the following example, 20 modules are loaded, each of them sources the same Tcl file:
$ syscall_list=close,fcntl,ioctl,newfstatat,openat,read,readlink $ strace -f -e $syscall_list -c $MODULES_CMD bash load foo/20 % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 31.48 0.000781 1 466 read 28.58 0.000709 5 131 16 openat 14.19 0.000352 2 142 3 newfstatat 9.71 0.000241 1 124 close 8.02 0.000199 0 212 211 readlink 4.55 0.000113 1 67 47 ioctl 3.47 0.000086 1 60 fcntl ------ ----------- ----------- --------- --------- ---------------- 100.00 0.002481 2 1202 277 total
When sourced file is cached, it is only read once which saves a substantial amount of I/O operations:
$ module config source_cache 1 $ strace -f -e $syscall_list -c $MODULES_CMD bash load foo/20 % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 34.41 0.000523 4 112 16 openat 27.37 0.000416 0 428 read 11.84 0.000180 1 122 3 newfstatat 11.51 0.000175 1 105 close 7.11 0.000108 2 47 27 ioctl 5.99 0.000091 0 92 91 readlink 1.78 0.000027 0 40 fcntl ------ ----------- ----------- --------- --------- ---------------- 100.00 0.001520 1 946 137 total
v5.3
This new version is backward-compatible with previous version 5 release. It fixes bugs but also introduces new functionalities that are described in this section. See the 5.3 release notes for a complete list of the changes between Modules v5.2 and v5.3.
Module cache
A module cache file can be created under each modulepath directory with new
cachebuild sub-command. Cache file is named .modulecache and
contains in one file all modulefiles and modulercs found in modulepath
directory.
When cache file is available, module search mechanism uses this file rather walking through the content of modulepath directory. I/O operations are saved this way which reduces search processing time.
When searching for available modules without cache, each file contained in enabled modulepaths is opened to check if it is a modulefile or not. Such checks lead to a large number of I/O operations on large module setup like in the below example where a total of 1051 modulefiles are available:
$ module -o "" avail -t | wc -l 1051 $ syscall_list=access,close,getdents64,newfstatat,openat,read $ strace -f -e $syscall_list -c $MODULES_CMD bash avail % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 31.09 0.003776 2 1424 9 openat 28.56 0.003469 2 1649 3 newfstatat 14.08 0.001710 1 1421 close 11.85 0.001439 3 460 getdents64 10.88 0.001321 0 1505 read 3.54 0.000430 4 107 5 access ------ ----------- ----------- --------- --------- ---------------- 100.00 0.012145 1 6566 17 total
After building cache file for every enabled modulepaths in this example setup, a lot of I/O operations are saved when searching for available modules:
$ module cachebuild Creating /path/to/modulefiles/.modulecache Creating /path/to/modulefiles.2/.modulecache Creating /path/to/modulefiles.3/.modulecache $ module config cache_buffer_bytes 1000000 $ strace -f -e $syscall_list -c $MODULES_CMD bash avail % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 70.19 0.000544 2 255 read 13.16 0.000102 2 38 9 openat 8.90 0.000069 1 35 close 6.06 0.000047 1 31 2 newfstatat 1.68 0.000013 1 11 2 access ------ ----------- ----------- --------- --------- ---------------- 100.00 0.000775 2 370 13 total
A significant execution time drop may be noticed, especially if modulepath directories are stored on heavily loaded network filesystem.
To further optimize I/O operation count, the cache_buffer_bytes
configuration option can be set like in the above example to use fewer number
of read operation to load cache file content.
To build cache file, user should be granted write access on modulepath directory. Modulefiles or directories that are not accessible for everyone are not recorded in cache. An indication is saved instead to test these limited access elements when cache is loaded to determine if they are available to currently running user.
Cache file can be ignored with --ignore-cache command line switch or
more permanently with ignore_cache configuration option.
Cache file is valid indefinitely by default but cache_expiry_secs
configuration option can be used to define the number of seconds a cache file
is considered valid after being generated. Expired cache file is ignored.
Cache file of enabled modulepaths can be deleted all at once with
cacheclear sub-command.
Querying available module variants
A new mechanism named Extra match search is introduced to evaluate modulefiles during a module search to find those matching an extra query on a variant value, a dependency or an environment variable definition.
During this specific evaluation, modulefiles are interpreted in scan mode to collect the different Tcl modulefile commands they use. Special care should be given when writing modulefiles to ensure they cope with such evaluation mode.
Extra match search mechanism is available on avail,
whatis and paths sub-commands.
With this new mechanism, it is possible to list all available variant defined in modulefiles with their associated values:
$ module config avail_output modulepath:alias:dirwsym:sym:tag:key:variant $ module config variant_shortcut toolchain=% $ module avail --------------------- /path/to/modulefiles --------------------- bar/1.0{%a,b} foo/1.0{%a} qux/1.0{%a,b} bar/2.0{%b} foo/2.0{%a,b,c} qux/2.0{%b,c} Key: modulepath {%value}={toolchain=value} default-version {variant=value}
You can also search for modules defining a specific variant value:
$ module avail %a --------------------- /path/to/modulefiles --------------------- bar/1.0{%a,b} foo/1.0{%a} foo/2.0{%a,b,c} qux/1.0{%a,b} Key: modulepath {%value}={toolchain=value} default-version {variant=value}
Note
As extra match search implies additional modulefile evaluations, it is advised to build and use Module cache to improve search speed.
Two new elements, variant and variantifspec, are added to the allowed
value list of avail_output and avail_terse_output
configuration options. The latter is set in the default value list of both
options. When variant is set, variants and their possible values are
reported along module they are associated to. When variantifspec is set,
available variants are reported only if a variant is specified in search
query.
$ module config --reset avail_output $ module config avail_output Modules Release 5.3.0 (2023-05-14) - Config. name ---------.- Value (set by if default overridden) --------------- avail_output modulepath:alias:dirwsym:sym:tag:variantifspec:key $ module avail foo --------------------- /path/to/modulefiles --------------------- foo/1.0 foo/2.0 Key: modulepath $ module avail foo %a --------------------- /path/to/modulefiles --------------------- foo/1.0{%a} foo/2.0{%a,b,c} Key: modulepath {%value}={toolchain=value} default-version {variant=value}
Extra specifiers
Extra specifiers are introduced to query content of modulefiles. They can be
specified with element:name syntax as part of module specification on module
search commands (avail, paths and and whatis).
Extra specifiers trigger Extra match search mechanism when found in module specification. Available modulefiles are evaluated in scan mode to collect the different Tcl modulefile commands they use.
$ module avail variant:toolchain --------------------- /path/to/modulefiles --------------------- bar/1.0 bar/2.0 foo/1.0 foo/2.0 qux/1.0 qux/2.0
In the above example, all modulefiles defining a toolchain variant are
returned.
Most Tcl modulefile commands can be queried with extra specifiers:
variant, setenv, unsetenv, append-path, prepend-path,
remove-path, pushenv, complete, uncomplete, set-alias,
unset-alias, set-function, unset-function, chdir, family,
prereq, prereq-any, prereq-all, depends-on, always-load,
load, load-any, try-load, switch, switch-on,
switch-off, conflict and unload. Commands that handle environment
variables may be aliased envvar. Commands that define a module requirement
may be aliased require and those that define a module incompatibility may
be aliased incompat.
When several extra specifiers are set in query, modules returned are those
matching both conditions. In the following example, all modulefiles
interacting with PATH environment variable and requiring foo
module are returned.
$ module avail envvar:PATH require:foo --------------------- /path/to/modulefiles --------------------- bar/1.0 bar/2.0
Extra specifiers related to module requirement or incompatibility may leverage
the Advanced module version specifiers syntax. On following example,
modulefiles returned are those defining a requirement on foo module with
version higher or equal to 1.2 and variant toolchain=a selected.
$ module avail "require:foo@1.2: toolchain=a" --------------------- /path/to/modulefiles --------------------- bar/1.0
Note
Module aliases or symbolic versions used either in modulefile definitions or as extra specifier values are not resolved.
Append or subtract elements to current option value
For command-line switches and configuration options whose value is a
colon-separated list, it is now possible to append or subtract elements to the
current value. With a + prefix elements are appended and with a -
prefix elements are subtracted.
This new feature applies to --output/-o command-line
switches and avail_output, avail_terse_output,
list_output, list_terse_output, colors,
protected_envvars, shells_with_ksh_fpath,
tag_abbrev, tag_color_name, variant_shortcut
configuration options.
For instance, to output available foo modules without modulepath and tag information:
$ module -o -modulepath:tag avail foo foo/1.0 foo/2.0
On following example, terse output mode of list sub-command is permanently updated to report variant information:
$ module config list_terse_output Modules Release 5.3.0 (2023-05-14) - Config. name ---------.- Value (set by if default overridden) --------------- list_terse_output header $ module config list_terse_output +variant $ module config list_terse_output Modules Release 5.3.0 (2023-05-14) - Config. name ---------.- Value (set by if default overridden) --------------- list_terse_output header:variant (env-var)
v5.2
This new version is backward-compatible with previous version 5 release. It fixes bugs but also introduces new functionalities that are described in this section. See the 5.2 release notes for a complete list of the changes between Modules v5.1 and v5.2.
Optional requirements
The --optional option has been added to the prereq,
prereq-all, depends-on and always-load modulefile
commands to indicate that specified requirement is optional. An automatic
load attempt is also performed for optional requirements. If requirement is
not found or cannot be loaded, the dependency is yet considered satisfied as
it is optional.
$ module show foo ------------------------------------------------------------------- /path/to/modulefiles/foo: prereq --optional bar ------------------------------------------------------------------- $ module load foo Loading foo Loading requirement: bar
If the optional requirement is unloaded or loaded afterward, the dependent
module is automatically reloaded thanks to the auto_handling
mechanism.
$ module unload bar Unloading bar Unloading dependent: foo Reloading dependent: foo $ module list Currently Loaded Modulefiles: 1) foo $ module load bar Loading bar Unloading dependent: foo Reloading dependent: foo
Modules loaded by other modules with the module try-load
command are now considered optional requirements. Dependent module can be
loaded without the try-load modules, but now it gets automatically reloaded
if try-load module is loaded afterward, to take it into account.
Linting modulefiles
Static analysis of modulefile, modulerc and global/user rc is now possible
with lint sub-command. It relies on an external program defined with
tcl_linter configuration option. Modules or files specified on the
command-line are resolved then passed to the Tcl linter program.
$ cat /path/to/modulefiles/foo/1.0 #%Module if {"str" eq} { else { } $ module lint foo/1.0 Linting /path/to/modulefiles/foo/1.0 ERROR line 2: Could not complete statement. One close brace would complete the first line One close brace would complete at end of line 4. One close brace would complete the script body at line 5. Assuming completeness for further processing. ERROR line 2: Bad expression: missing operand at _@_ in expression ""str" eq_@_" WARNING line 3: Unknown command "else" NOTICE line 4: Close brace not aligned with line 3 (1 0)
Nagelfar is the Tcl linter recommended for Modules and set by default. This
default can be changed at installation time with --with-tcl-linter
and --with-tcl-linter-opts options. It can also be configured later
on through tcl_linter config option.
Specific syntax databases and plugins for Nagelfar are added by Modules to
precisely lint modulefile commands syntax in addition to regular Tcl syntax.
The installation of these specific files is controlled with
--enable-nagelfar-addons option (enabled by default). Their
location is controlled by the --nagelfardatadir option.
$ module lint bar@:1 /path/to/modulefiles/.modulerc Linting /path/to/modulefiles/.modulerc ERROR line 35: Wrong number of arguments (3) to "module-alias" ERROR line 41: Wrong number of arguments (3) to "module-virtual" Linting /path/to/modulefiles/bar/1.2 WARNING line 19: Unknown command "unk" $ module lint ~/.modulerc Linting /home/user/.modulerc WARNING line 2: Command "setenv" should not be be used in global rc file
lint sub-command outputs messages returned by the Tcl linter
program. Nagelfar produces NOTICE, WARNING and ERROR messages. If linter does
not report a thing, lint sub-command will be silent, unless if the
--verbose/-v is set.
$ module lint /path/to/modulefiles/bar/.version bar/1.4 $ module lint -v /path/to/modulefiles/bar/.version bar/1.4 Linting /path/to/modulefiles/bar/.version Linting /path/to/modulefiles/bar/1.4
When no file is specified to lint sub-command, all the global/user
rc files and all the modulefiles and modulercs from enabled modulepaths are
analyzed. If the --all/-a option is set, all hidden
modulefiles are also linted.
$ module lint Linting /home/user/.modulerc WARNING line 2: Command "setenv" should not be be used in global rc file Linting /path/to/modulefiles/.modulerc ERROR line 35: Wrong number of arguments (3) to "module-alias" ERROR line 41: Wrong number of arguments (3) to "module-virtual" Linting /path/to/modulefiles/bar/1.2 WARNING line 19: Unknown command "unk" ...
To use Nagelfar as Tcl linter for Modules, this open source tool has to be
installed on your system. When installing from tarball distribution, make sure
nagelfar.tcl command is found through a PATH lookup or
that tcl_linter option is set to its full path location.
Nagelfar is also made available as a RPM package in EPEL and Fedora
repositories.
mod-to-sh sub-command
New sub-command is added to translate modulefile into shell code:
mod-to-sh. It evaluates modulefiles passed as argument and produces
code for specified shell.
$ cat /path/to/modulefiles/foo #%Module setenv FOO value set-function foo {echo foo} $ module mod-to-sh bash foo FOO=value; export FOO; foo () { echo foo; }; export -f foo;
Designated modulefiles are evaluated as if they were loading. But instead of producing shell code that is evaluated in current shell session, module command outputs this shell code.
$ cat /path/to/modulefiles/bar #%Module setenv BAR othervalue set-alias bar {echo bar} $ module mod-to-sh fish foo bar set -xg FOO value; set -xg BAR othervalue; alias bar echobar; function foo; echo foo; end; $ module list No Modulefiles Currently Loaded.
All shells supported by modulecmd.tcl script are supported by
mod-to-sh.
$ module mod-to-sh python foo bar
import os
os.environ['FOO'] = 'value'
os.environ['BAR'] = 'othervalue'
Initial environment
When Modules initializes, it evaluates the initrc and
modulespath configuration files to enable default modulepaths and load
default modules. Initial environment corresponds to the environment state
after this initialization.
Initial environment is now saved in an environment variable
(__MODULES_LMINIT) in current shell session to remember what are the
initial modulepaths and initial modules with their tags and variants if any.
reset sub-command is introduced, in a similar fashion than on
Lmod, to restore the initial environment. Here, reset relies on
the collection mechanism based and the content of
__MODULES_LMINIT. Currently enabled modulepaths and loaded modules
are respectively unused and unloaded to use the modulepaths and load the
modules with tags and variants as described by initial environment.
$ module list Currently Loaded Modulefiles: 1) foo/1.0 2) bar/1.0 $ module switch bar/1.0 qux/1.0 $ module reset Unloading qux/1.0 Loading bar/1.0
restore sub-command has been adapted to reinitialize the environment
to its initial state when no collection name is provided and no default
collection exists or if __init__ virtual collection name is provided.
It is possible to view the content of the initial environment with
saveshow sub-command. It is displayed when no argument is provided
and no collection exists or if __init__ name is provided.
$ module saveshow __init__ ------------------------------------------------------------------- initial environment: module use --append /path/to/modulefiles module load foo/1.0 module load bar/1.0 -------------------------------------------------------------------
Users have the ability to define what is their initial environment state and
thus adapt the behavior of reset sub-command with
reset_target_state configuration option. Default value is
__init__ and it corresponds to the behavior described above. When set to
__purge__, a purge command is performed when resetting. Any
other value corresponds to the name of a collection to restore.
$ module config reset_target_state __purge__ $ module reset Unloading bar/1.0 Unloading foo/1.0
Stashing environment
The ability to stash current environment is added with the introduction of the
stash sub-command. When called current environment is saved in a
stash collection then initial environment is restored.
$ module list Currently Loaded Modulefiles: 1) bar/2.0 2) foo/2.0 $ module stash Unloading foo/2.0 Unloading bar/2.0 $ module list No Modulefiles Currently Loaded.
Sub-commands are added to specifically handle stash collections. Their names
are prefixed with stash, like stashlist to list existing stash
collections or stashshow to display their content.
$ module stashlist Stash collection list: 0) stash-1665377597432 1) stash-1664946764252 $ module stashshow ------------------------------------------------------------------- /home/user/.module/stash-1665377597432: module use --append /path/to/modulefiles module load bar module load foo -------------------------------------------------------------------
Stash collections can be designated on sub-commands by their collection name
or stash index. Most recent stash collection has index 0, the one after is
designated with index 1, and so on. When no stash collection is specified,
most recent one is assumed.
$ module stashshow 1 ------------------------------------------------------------------- /home/user/.module/stash-1664946764252: module use --append /path/to/modulefiles module load foobar -------------------------------------------------------------------
Stash collections are restored with the stashpop sub-command. It
changes the user environment to match the stash definition, then it deletes
the stash collection file.
$ module stashpop Loading bar/2.0 Loading foo/2.0 $ module stashlist Stash collection list: 0) stash-1664946764252
Stash collections can be deleted one by one with stashrm sub-command
or all together with stashclear.
$ module stashrm $ module stashlist No stash collection.
Siteconfig hook variables
Several Tcl variables are introduced for Site-specific configuration
script to define specific commands and variables in the evaluation context of
modulefiles and modulercs. These commands and variables setup in
siteconfig.tcl can be used in modulefile or modulerc. Sites can easily
extend modulefile and modulerc syntax with specific elements.
modulefile_extra_cmds variable defines a list of commands to expose
in the modulefile evaluation context and the associated procedure to run when
this command is called. This variable has to be defined in
siteconfig.tcl located for instance at /etc/environment-modules/siteconfig.tcl.
In the following example modulefile_extra_cmds is used to define
the sys command and bound it to the sys procedure that is also defined
in siteconfig.tcl.
proc sys {mode} {
switch -- $mode {
name { return myhost-$::tcl_platform(machine) }
default { error "Unknown mode '$mode'" }
}
}
set modulefile_extra_cmds {sys sys}
Once siteconfig.tcl is setup, the sys command can be called by
modulefiles. In the following example it is used to determine the application
path.
$ cat /path/to/modulefiles/foo/1.2 #%Module append-path PATH /path/to/apps/foo-1.2/[sys name]/bin $ module show foo/1.2 ------------------------------------------------------------------- /path/to/modulefiles/foo/1.2: append-path PATH /path/to/apps/foo-1.2/myhost-x86_64/bin -------------------------------------------------------------------
modulerc_extra_cmds follows the same approach than
modulefile_extra_cmds and makes specific commands available during
modulerc evaluation.
modulefile_extra_vars variable defines a list of variables to
expose in the modulefile evaluation context and their associated value. This
variable has to be defined in siteconfig.tcl.
In the following example modulefile_extra_vars is used to define
the APP_ROOT variable with /path/to/apps as value.
set modulefile_extra_vars {APP_ROOT /path/to/apps}
Once siteconfig.tcl is setup, the APP_ROOT variable can be used in
modulefiles.
$ cat /path/to/modulefiles/bar/2.1 #%Module append-path PATH $APP_ROOT/bar-2.1/[sys name]/bin $ module show bar/2.1 ------------------------------------------------------------------- /path/to/modulefiles/bar/2.1: append-path PATH /path/to/apps/bar-2.1/myhost-x86_64/bin -------------------------------------------------------------------
modulerc_extra_vars follows the same approach than
modulefile_extra_vars and makes specific variables available during
modulerc evaluation.
v5.1
This new version is backward-compatible with previous version 5 release. It fixes bugs but also introduces new functionalities that are described in this section. See the 5.1 release notes for a complete list of the changes between Modules v5.0 and v5.1.
Control output redirection
Since version 4.0, the module function is initialized differently on sh, bash, ksh, zsh and fish shells when their session is found interactive. In such situation module redirects its output from stderr to stdout. Once initialized the redirection behavior is inherited in sub-sessions.
The redirect_output configuration option is introduced in version
5.1, to supersede the default behavior set at initialization time.
$ module load unknown >/dev/null $ module config redirect_output 0 $ module load unknown >/dev/null ERROR: Unable to locate a modulefile for 'unknown'
The --redirect and --no-redirect command-line switches are
also added to change the output redirection behavior for a single command:
$ module load unknown --redirect >/dev/null $ module load unknown --no-redirect >/dev/null ERROR: Unable to locate a modulefile for 'unknown'
Change modulefile command behavior
Depending on the evaluation mode of the modulefile (e.g. load, unload,
display, etc) commands have different behavior. Most common example is the
setenv command that sets an environment variable when modulefile is
loaded and unsets it when it is unloaded. A different behavior may be wished
sometimes for commands. This is why options are introduced for some modulefile
commands to control what happens on particular evaluation mode.
The --return-value option is added to the getenv and
getvariant modulefile commands to ensure that the value of the
designated environment variable or variant is returned even if modulefile is
evaluated in display mode:
$ cat /path/to/modulefiles/foo/1.0 #%Module5.1 if {[getenv --return-value VAR] eq {}} { setenv VAR value } $ module display foo/1.0 ------------------------------------------------------------------- /path/to/modulefiles/foo/1.0: setenv VAR value -------------------------------------------------------------------
--remove-on-unload, --append-on-unload, --prepend-on-unload and
--noop-on-unload options are added to the remove-path and
module unuse modulefile commands to control the behavior
applied when modulefile is unloaded. With these options it is possible for
instance to restore the paths unset at load time or to set other paths:
$ module display bar/1.0 ------------------------------------------------------------------- /path/to/modulefiles/bar/1.0: module unuse --prepend-on-unload /path/to/dir1 module use /path/to/dir2 ------------------------------------------------------------------- $ module use Search path for module files (in search order): /path/to/dir1 /path/to/modulefiles $ module bar/1.0 $ module use Search path for module files (in search order): /path/to/dir2 /path/to/modulefiles $ module unload bar/1.0 $ module use Search path for module files (in search order): /path/to/dir1 /path/to/modulefiles
Following the same trend, the --unset-on-unload and --noop-on-unload
options are added to the unsetenv modulefile command to be able to
choose between unsetting variable, setting a value or performing no operation
when modulefile is unloaded.
Reducing number of I/O operations
A new configuration option named mcookie_check is introduced to
control the verification made to files to determine if they are modulefiles.
By default this configuration option is set to always and when searching
for modulefiles within enabled modulepaths each file below these directories
is opened to check if it starts with the Modules magic cookie (i.e.,
#%Module file signature).
These historical checks lead to a large number of I/O operations on large module setup like in the below example where a total of 1098 modulefiles are available:
$ module -o "" avail -t | wc -l 1098 $ module config mcookie_check always $ strace -f -e open,openat,read,close -c $MODULES_CMD bash avail ... % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 44.29 0.044603 25 1734 166 open 34.15 0.034389 16 2056 close 11.87 0.011949 24 483 5 openat 9.69 0.009761 4 2146 read ------ ----------- ----------- --------- --------- ---------------- 100.00 0.100702 6419 171 total
For each file, 3 I/O operations (open, read and close) are
achieved to determine if it is a modulefile and include it in search results.
When modulefiles are located in a shared filesystem concurrently accessed by
hundreds of users, a module avail command may take some time to finish.
When setting the mcookie_check configuration option to the eval
value, files are not checked anymore when searching for modulefiles, only when
evaluating them. All files under modulepaths are considered modulefiles, so
the content of these directories must be carefully checked to use this
mcookie_check mode which lead to a significant reduction of I/O
operations:
$ module config mcookie_check eval $ strace -f -e open,openat,read,close -c $MODULES_CMD bash avail ... % time seconds usecs/call calls errors syscall ------ ----------- ----------- --------- --------- ---------------- 30.56 0.013717 14 944 close 28.76 0.012911 21 612 156 open 26.41 0.011857 24 483 5 openat 14.26 0.006403 6 1034 read ------ ----------- ----------- --------- --------- ---------------- 100.00 0.044888 3073 161 total
A substantial reduction of execution time may be noticed depending on the
storage setup used to host the modulepath directories. A special care should
be given to the content of these directories to ensure they only contain
modulefiles (see MODULES_MCOOKIE_CHECK).
See the Reduce I/O load cookbook recipe to learn additional features of Modules that could be leveraged to lower the number of I/O operations.
Shell command completion
New modulefile commands complete and uncomplete are added to
get the ability to respectively define and unset command completion. bash,
tcsh and fish shells are supported.
> module display foo ------------------------------------------------------------------- /path/to/modulefiles/foo/1.0: append-path PATH /path/to/foo-1.0/bin complete fish foo {-s V -l version --description 'Command version'} complete fish foo {-s h -l help --description 'Command help'} ------------------------------------------------------------------- > module load foo > foo -<TAB> -h --help (Command help) -V --version (Command version)
sh-to-mod sub-command and source-sh modulefile command have
also been updated to track shell completion changes.
$ module sh-to-mod bash /path/to/foo-1.0/share/setup-env.sh #%Module complete bash foo {-o default -F _foo} append-path PATH /path/to/foo-1.0/bin set-function _foo { ...bash completion code...}
Lmod Tcl modulefile support
With this new version, Modules now supports Tcl modulefiles written for Lmod, the alternative module implementation developed in Lua. Such modulefiles can be safely evaluated by Modules without raising error.
Support has been added for the following modulefile commands introduced by
Lmod: depends-on, prereq-any, always-load,
module load-any, pushenv, require-fullname
and family.
The Compatibility with Lmod Tcl modulefile section in the modulefile man page describes the differences existing between the two implementations.
Note that when processing a family command, the
LMOD_FAMILY_<NAME> environment variable is defined by Modules to
be compatible with existing modulefiles or scripts relying on such variable.
More tagging capabilities
The new --tag option helps to define extra tags onto a loading
module. These tags comes in addition to those inherited from the module state
or those associated with the module-tag modulefile command.
The --tag option is available on load, load-any,
switch and try-load sub-commands and on
always-load, depends-on, module, prereq,
prereq-all and prereq-any modulefile commands.
Informational messages of module evaluation have been updated to mention in
module denomination the tags applying to it, as it is done in list
sub-command output:
$ module load -v --tag=sticky:bar foo/1.0 Loading foo/1.0 <bar>
In case the designated module is already loaded, the additional tags are added to the list of tags already applied to this module.
$ module list Currently Loaded Modulefiles: 1) foo/1.0 $ module load -v --tag=sticky:bar foo/1.0 Tagging foo/1.0 <bar>
The keep-loaded tag is introduced in this version. It avoids an
auto-loaded module to get automatically unloaded when its dependent modules
are unloaded. This new tag can be set with the module-tag modulefile
command or when module is loaded with the always-load modulefile
command. Default tag_abbrev configuration option has been updated
to add the kL abbreviation for keep-loaded tag. Default dark and light
color palettes have been updated too.
$ module show bar/1.0 ------------------------------------------------------------------- /path/to/modulefiles/bar/1.0: always-load foo/1.0 ------------------------------------------------------------------- $ module load bar/1.0 Loading bar/1.0 Loading requirement: foo/1.0 $ module unload bar/1.0 $ module list Currently Loaded Modulefiles: 1) foo/1.0 Key: auto-loaded keep-loaded
When saving a collection, the tags defined with --tag option are
recorded to set them again when collection is restored. Tags resulting from
module load state, like auto-loaded and keep-loaded, are also
recorded.
$ module load --tag=sticky bar/1.0 Loading bar/1.0 Loading requirement: foo/1.0 $ module save $ module saveshow ------------------------------------------------------------------- /home/user/.module/default: module use --append /path/to/modulefiles module load --tag=auto-loaded:keep-loaded foo module load --tag=sticky bar -------------------------------------------------------------------
The collection_pin_tag configuration option is added to record in
collection all tags set on loaded modules. This configuration option is
disabled by default.
Note
Collection saved now starts with a #%Module5.1 file signature if
--tag option is recorded in it. Such collection could only be
handled by Modules version 5.1 and above.
v5.0
With this new major version the module experience has been updated to benefit by default from all the advanced behaviors and features developed over the Modules 4 versions. Modules 5.0 also introduces some breaking changes to improve the consistency of the whole solution. See the 5.0 release notes for a complete list of the changes between Modules v4.8 and v5.0. The changes document gives an in-depth view of the modified behaviors.
Upgraded default configuration
Release after release, new advanced features were added on Modules 4. They were set off by default to avoid breaking change during the version 4 cycle. With the move to a new major release, these features are set on to improve by default usages for everybody. These features enabled by default are:
Automated module handling mode which provides the automatic dependency resolution when loading and unloading modules
$ module load foo/1.0 Loading foo/1.0 Loading requirement: bar/1.0
Extended default that enables to select a module when the first number in its version is specified
$ module load -v foo/1 Loading foo/1.2.3
Advanced module version specifiers, an improved syntax to designate module version in range or list and module variant
$ module load foo@:2.2 %gcc11 Loading foo/2.1{%gcc11} Loading requirement: bar/1.2{-debug:%gcc11}
Colored output to graphically enhance parts of the produced output to improve readability
$ ml av ------------------ /path/to/modulefiles ------------------ bar/1.0 bar/2.0 foo/1.0 foo/2.0 foo/2.2 Key: modulepath module-alias sticky default-version forbidden
Specify modules in a case insensitive manner search that matches modules using a different character case than the one expressed in search query
$ ml av liba ------------------ /path/to/modulefiles ------------------ LibA/1.0 LibA/2.0
Some other features that were enabled by default during the Modules 4 cycle
have been turned off as they may not be useful for basic usages. Among other
things setting off the following features makes the definition of the
module function simpler. Even if off by default, these features
can now be enabled once Modules is installed through the initrc
configuration file.
Set shell startup files to ensure the module command is defined once shell has been initialized. See the
set_shell_startupconfiguration option to activate.Quarantine mechanism that protects the module command run-time environment from side effect coming from the current environment definition. See the
quarantine_supportconfiguration option to activate.Silent shell debug which disables the debugging property set on current shell session for the duration of the module command. See the
silent_shell_debugconfiguration option to activate.
Removing compatibility version
The ability to co-install version 3.2 of Modules along newer version is
discontinued. The installation option --enable-compat-version,
switchml shell function and MODULES_USE_COMPAT_VERSION
environment variables are thus removed.
The interesting features of Modules 3.2 that were missing in the
initial Modules 4 release in 2017 have been reintroduced progressively (like
clear sub-command or --icase search). With Modules 5.0,
the refresh sub-command is even changed to the behavior it had on
Modules 3.2. So it is a good time for the big jump.
If you are still using Modules 3.2, please refer to the Changes between versions document that describes the differences of this version compared to the newer releases.
Improving Modules initialization
Modules initialization files are now installed by default in the etc
directory designated by the --etcdir installation option. The
initialization configuration file is named initrc in this directory,
and the modulepath-specific configuration file is named modulespath.
When both files exist, now they are both evaluated instead of just the
modulespath file.
Modules magic cookie (i.e., #%Module file signature) is now required at
the start of initrc. An error is produced if the magic cookie is
missing or if the optional version number placed after the cookie string is
higher than the version of the modulecmd.tcl script in use.
Note that initrc configuration file can host more than
module use and module load commands.
module configuration can also be achieved with this file through
the use of module config commands.
Modules initialization has been enhanced for situations where a module environment is found already defined. In this case the loaded modules are automatically refreshed which is useful to re-apply the non-persistent environment configuration (i.e., shell alias and function that are not exported to the sub-shell). For instance when starting a sub-shell session it ensures that the loaded environment is fully inherited from parent shell:
$ ml show foo/1.0 ------------------------------------------------------------------- /path/to/modulefiles/foo/1.0: set-alias foo {echo foo} ------------------------------------------------------------------- $ ml foo/1.0 $ alias foo alias foo='echo foo' $ bash $ ml Currently Loaded Modulefiles: 1) foo/1.0 $ alias foo alias foo='echo foo'
Simplifying path-like variable reference counting
The reference counting mechanism used for path-like environment variable enables to determine if a path entry has been added several times (by several loaded modules for instance) to know whether or not this path entry should be unset when unloading a module. Entry is not removed if multiple loaded modules rely on it.
The mechanism is not applied anymore to the Modules-specific path variables
(like LOADEDMODULES) as an element entry in these variables cannot
be added multiple times without duplication. For instance, a given module name
and version cannot be added twice in LOADEDMODULES as this module is
only loaded once. With this change a thinner environment is produced by
module. An exception is made for MODULEPATH environment
variable where the mechanism still applies.
$ $MODULES_CMD bash load foo/2.0
_LMFILES_=/path/to/modulefiles/foo/2.0; export _LMFILES_;
LOADEDMODULES=foo/2.0; export LOADEDMODULES;
__MODULES_LMTAG=foo/2.0&mytag; export __MODULES_LMTAG;
test 0;
Reference counting mechanism has also been simplified for entries in path-like
variable that are only referred once. For such entries no entry is set in the
reference counting variable (which are now called
__MODULES_SHARE_<VAR>). A reference count entry is set only if the
entry in the path-like variable is referred more than one time.
$ ml foo/3.0 $ echo $PATHVAR /path/to/dir1 $ echo $__MODULES_SHARE_PATHVAR $ ml bar/1.0 $ echo $PATHVAR /path/to/dir1 $ echo $__MODULES_SHARE_PATHVAR /path/to/dir1:2 $ ml -foo/3.0 $ echo $PATHVAR /path/to/dir1 $ echo $__MODULES_SHARE_PATHVAR $
When the use and unuse module sub-commands are not called
during a modulefile evaluation, the reference counter associated with each
entry in MODULEPATH environment variable is ignored. In such
context, a module use will not increase the reference counter
of a path entry already defined and a module unuse will
remove specified path whatever its reference counter value. Same change applies
for append-path, prepend-path and remove-path
module sub-commands when called from the command-line.
$ echo $MODULEPATH /path/to/modulefiles $ echo $__MODULES_SHARE_MODULEPATH /path/to/modulefiles:2 $ ml use /path/to/modulefiles $ echo $__MODULES_SHARE_MODULEPATH /path/to/modulefiles:2 $ ml unuse /path/to/modulefiles $ echo $MODULEPATH $ echo $__MODULES_SHARE_MODULEPATH $
v4.8
This new version is backward-compatible with previous version 4 releases. It fixes bugs but also introduces new functionalities that are described in this section. See the 4.8 release notes for a complete list of the changes between Modules v4.7 and v4.8.
Editing modulefiles
edit sub-command is introduced to give the ability to open
modulefiles in a text editor. Modulefiles can be specified like with any other
sub-command: using regular, symbolic or aliased names or using advanced
version specifiers.
$ ml edit foo
edit sub-command resolves the path toward the designated modulefile
then call configured text editor to open this modulefile with it. Below, the
modulefile is opened with the vi command:
#%Module
module-whatis [module-info name]
setenv PATH /path/to/foo-1.0/bin
~
~
~
"/path/to/modulefiles/foo/1.0" 3L, 42B 1,1 All
The editor configuration option controls the editor command to use.
This option can be configured at installation time with the
--with-editor installation option. If not set, editor
configuration option is set by default to vi.
editor configuration option can be changed with the
config sub-command. Which sets the MODULES_EDITOR
environment variable.
The VISUAL or the EDITOR environment variables override
the default value of editor configuration option but are overridden
by the MODULES_EDITOR environment variable.
Using version range in version list
The Advanced module version specifiers mechanism has been improved to allow the use of version range (@:version, @vers1:vers2 or @version:) within version list (@version1,version2,...).
It is now possible to write for instance mod@:1.2,1.4:1.6,1.8: to
designate all versions of module mod, except versions 1.3 and 1.7.
This improvement is available where the advanced version specifier syntax is supported. Thus it can be either used from the command-line or when writing modulefiles, for instance to hide or tag modules or to declare requirements.
Try module load with no complain if not found
Add the try-load sub-command that tries to load the modulefile
passed as argument, like the load sub-command, but does not raise an
error if this modulefile cannot be found.
$ module load unknown ERROR: Unable to locate a modulefile for 'unknown' $ echo $? 1 $ module try-load unknown $ echo $? 0 $ module list No Modulefiles Currently Loaded.
This sub-command first introduced by the Lmod project is added to Modules
to improve the compatibility between the two module implementations.
try-load is also available within modulefile context to continue the
evaluation of a modulefile in case no module is found in its attempt to load
another modulefile
$ module display foo/1.0 ------------------------------------------------------------------- /path/to/modulefiles/foo/1.0: module try-load unknown/1.0 ------------------------------------------------------------------- $ module load foo/1.0 $ module list Currently Loaded Modulefiles: 1) foo/1.0
Module variants
Module variants is a new mechanism that allows to pass arguments to evaluated modulefiles in order to achieve different environment variable or module requirement setup with a single modulefile.
Variant specification relies on the Advanced module version specifiers mechanism, which leverages the variant syntax of the Spack package manager:
$ module config advanced_version_spec 1 $ module load -v bar/1.2 toolchain=a -debug Loading bar/1.2{-debug:toolchain=a}
Variants are defined in modulefile with the variant command, which
defines the variant type and its accepted values:
#%Module4.8
variant toolchain a b c
variant --boolean --default off debug
# select software build depending on variant values
set suffix -[getvariant toolchain]
if {$ModuleVariant(debug)} {
append suffix -dbg
}
prepend-path PATH /path/to/bar-1.2$suffix/bin
prepend-path LD_LIBRARY_PATH /path/to/bar-1.2$suffix/lib
The bar/1.2 modulefile defines a toolchain variant, which accepts the
a, b and c values, and a debug Boolean variant, which is set
off by default. Once these two variants are declared, their value
specified on module designation are instantiated in the ModuleVariant
array variable which could also be queried with the getvariant
modulefile command. Selected variant values enable to define a specific
installation build path for the bar/1.2 software.
If a variant is not specified when designating module and if this variant is not declared with a default value, an error is obtained:
$ module purge $ module load bar@1.2 Loading bar/1.2 ERROR: No value specified for variant 'toolchain' Allowed values are: a b c
Once module is loaded, selected variants are reported on the list
sub-command output:
$ module load bar@1.2 toolchain=b $ module list Currently Loaded Modulefiles: 1) bar/1.2{-debug:toolchain=b} Key: {-variant}={variant=off} {variant=value}
Note
The default value of the --with-list-output installation
option has been updated to include variant information.
Variant specification could be used where the Advanced module version specifiers is supported. For instance a module may express a dependency over a specific module variant:
$ module show foo/2.1 toolchain=c ------------------------------------------------------------------- /path/to/modulefiles/foo/2.1: variant toolchain a b c prereq bar@1.2 toolchain={toolchain} prepend-path PATH /path/to/foo-2.1-{toolchain}/bin prepend-path LD_LIBRARY_PATH /path/to/foo-2.1-{toolchain}/lib -------------------------------------------------------------------
In this example, foo/2.1 module depends on bar/1.2 and the same toolchain variant should be selected for both modules in order to load two software builds that are compatible between each other.
$ module purge $ module config auto_handling 1 $ module load foo/2.1 toolchain=a Loading foo/2.1{toolchain=a} Loading requirement: bar/1.2{-debug:toolchain=a}
Variant shortcuts
The variant_shortcut configuration option is added to define
shortcut characters for easily specifying variants. Instead of writing the
variant name to specify it in module designation (e.g., name=value), the
shortcut associated to this variant could be used (i.e., <shortcut>value):
$ module purge $ module config variant_shortcut toolchain=% $ module load foo/2.1 %a Loading foo/2.1{%a} Loading requirement: bar/1.2{-debug:%a}
Configured shortcuts are also used to report the loaded variant on
list sub-command output (shortcuts are explained in key section):
$ module list Currently Loaded Modulefiles: 1) bar/1.2{-debug:%a} 2) foo/2.1{%a} Key: auto-loaded {-variant}={variant=off} {%value}={toolchain=value} {variant=value}
v4.7
This new version is backward-compatible with previous version 4 releases. It fixes bugs but also introduces new functionalities that are described in this section. See the 4.7 release notes for a complete list of the changes between Modules v4.6 and v4.7.
Determining module implementation and version
New Modules variables are introduced to determine during the evaluation of a
modulefile or a modulerc what module implementation is currently in use. The
ModuleTool variable corresponds to the name of the module
implementation and is set to Modules for this project. The
ModuleToolVersion variable corresponds to the version number of the
implementation (e.g. 4.7.0).
With these new variables it is possible to precisely know what module command is in use then adapt modulefile code to handle a specific behavior or leverage a new feature.
The modulefile command versioncmp is also introduced to provide a
simple way to compare two version strings and return if first version string
is less than, equal to or greater than second one.
if {[info exists ModuleTool] && $ModuleTool eq {Modules}
&& [versioncmp $ModuleToolVersion 4.7] >= 0} {
# here some code specific for Modules 4.7 and later versions
}
The ModuleTool and ModuleToolVersion variables and the
versioncmp modulefile command are supported by the Lmod project
starting version 8.4.8.
Symbolic version to designate module loaded version
When the Advanced module version specifiers is enabled, the loaded
symbolic version may be used to designate the currently loaded version of
specified module.
$ ml display foo@loaded ------------------------------------------------------------------- /path/to/modulefiles/foo/1.0: module-whatis foo/1.0 -------------------------------------------------------------------
If no version of specified module can be found loaded, an error is returned.
$ ml display foo@loaded ERROR: No loaded version found for 'foo' module
Hiding loaded modules
The --hidden-loaded option has been added to the module-hide
modulefile command and it indicates that designated hidden modules remain
hidden after being loaded.
$ cat /path/to/modulefiles/foo/1.0 #%Module module load bar $ cat /path/to/modulefiles/bar/.modulerc #%Module4.7 module-hide --soft --hidden-loaded bar
In this example, foo depends on bar which is set soft hidden and hidden once loaded. As a consequence, automated load of bar module will not be reported and bar/1.0 will not appear in loaded module list by default:
$ ml foo $ ml Currently Loaded Modulefiles: 1) foo/1.0
However bar/1.0 is loaded. Hidden loaded modules can be unveiled with the
--all/-a option set on the list sub-command.
hidden-loaded tag (abbreviated by default to H when colored output is
disabled) applies to such modules.
$ ml -a Currently Loaded Modulefiles: 1) bar/1.0 2) foo/1.0
To also get the informational messages about hidden loaded module automated
load or unload, the new verbosity level verbose2 can be used (with
-vv option for instance):
$ ml purge $ ml -vv foo Loading bar/1.0 Loading foo/1.0 Loading requirement: bar/1.0
Sticky modules
Module stickiness is introduced, in a similar fashion than on the Lmod project, to allow to glue modules to the loaded environment. A sticky module cannot be unloaded, unless if the unload action is forced or if the module reloads after being unloaded.
A modulefile is declared sticky by applying it the sticky tag with the
module-tag modulefile command.
$ cat /path/to/modulefiles/foo/.modulerc #%Module4.7 module-tag sticky foo/1.0 $ ml Currently Loaded Modulefiles: 1) foo/1.0 $ ml -foo Unloading foo/1.0 ERROR: Unload of sticky module 'foo/1.0' skipped $ ml Currently Loaded Modulefiles: 1) foo/1.0 $ ml --force -foo Unloading foo/1.0 WARNING: Unload of sticky module 'foo/1.0' forced $ ml No Modulefiles Currently Loaded.
Modulefile can also be defined super-sticky by applying the corresponding
module tag. Super-sticky module cannot be unloaded even if the unload action
is forced. It can only be unloaded if the module reloads afterward.
$ cat /path/to/modulefiles/bar/.modulerc #%Module4.7 module-tag super-sticky bar/1.0 $ ml Currently Loaded Modulefiles: 1) bar/1.0 $ ml purge Unloading bar/1.0 ERROR: Unload of super-sticky module 'bar/1.0' skipped $ ml purge -f Unloading bar/1.0 ERROR: Unload of super-sticky module 'bar/1.0' skipped $ ml Currently Loaded Modulefiles: 1) bar/1.0
Modulefiles targeted by a sticky or a super-sticky tag are colored on
avail and list sub-command outputs to indicate such tag
applies. If colored output is disabled a tag abbreviation is reported along
module designation (respectively S and sS).
In case the stickiness applies to the generic module name (and does not target a specific module version or version-set), one version of the sticky or super-sticky module can be swapped by another version of this same module:
$ cat /path/to/modulefiles/baz/.modulerc #%Module4.7 module-tag sticky baz $ ml Currently Loaded Modulefiles: 1) baz/2.0 $ ml switch baz/1.0 $ ml Currently Loaded Modulefiles: 1) baz/1.0
Explaining avail/list output
A Key section is added at the end of the avail and list
sub-commands output to give hints on the meaning of the graphical rendition
applied to elements or what the elements set in parentheses or chevrons along
module name stand for.
$ ml av ------------------ /path/to/modulefiles ------------------ foo/1.0 <oT> foo/2.0 foo/3.0 Key: loaded default-version sticky <oT>=othertag modulepath module-alias <module-tag>
Configuring avail/list output
New configuration options are introduced to control what content to output in
addition to modules names on the regular and terse output modes of the
avail and list sub-commands.
These new configuration options named avail_output,
avail_terse_output, list_output and
list_terse_output can be updated using the config
sub-command or set at installation time respectively with the
--with-avail-output, --with-avail-terse-output,
--with-list-output and --with-list-terse-output
configure options.
The four options accept a colon separated list of elements as value. Accepted
elements for the avail-related options are: modulepath,
alias, dirwsym, sym, tag and key. Accepted elements for
the list-related options are: header, idx, sym, tag
and key.
In the following example, default output configuration for the avail
sub-command is checked then module tags and key section are removed to get a
simpler output:
$ ml config avail_output Modules Release 4.7.0 (2021-02-19) - Config. name ---------.- Value (set by if default overridden) --------------- avail_output modulepath:alias:dirwsym:sym:tag:key $ ml av ------------------ /path/to/modulefiles ------------------ bar/1.0 bar/2.0 foo/1.0 foo/2.0 foo/2.2 Key: modulepath module-alias sticky default-version forbidden $ ml config avail_output modulepath:alias:dirwsym:sym $ ml av ------------------ /path/to/modulefiles ------------------ bar/1.0 bar/2.0 foo/1.0 foo/2.0 foo/2.2
The --output/-o switches are added to define a specific
output configuration for the duration of the associated command line. The
following example shows how to limit the content reported on a module
list to the loaded index and the symbolic versions in addition to
the module names:
$ ml Currently Loaded Modulefiles: 1) bar/1.0 2) foo/2.0 Key: default-version sticky $ ml -o idx:sym 1) bar/1.0 2) foo/2.0
When the new configuration options or command line switches are set to an empty value, the module names are the sole information reported:
$ ml -t -o ""
bar/1.0
foo/2.0
In case the modulepath element is withdrawn from the avail
sub-command output configuration, the available modules from all enabled
modulepaths are reported as a single list:
$ ml av --------------- /path/to/other/modulefiles --------------- baz/1.0 baz/2.0 ------------------ /path/to/modulefiles ------------------ bar/1.0 bar/2.0 foo/1.0 foo/2.0 foo/2.2 Key: modulepath module-alias sticky default-version forbidden $ ml av --output=alias:tag bar/1.0 baz/1.0 foo/1.0 foo/2.2 bar/2.0 baz/2.0 foo/2.0
Note
The avail_report_dir_sym and avail_report_mfile_sym locked
configuration options have been removed. Their behaviors can now be
obtained by respectively adding the dirwsym and sym elements to the
avail_output or avail_terse_output configuration
options.
v4.6
This new version is backward-compatible with previous version 4 releases. It fixes bugs but also introduces new functionalities that are described in this section. See the 4.6 release notes for a complete list of the changes between Modules v4.5 and v4.6.
sh-to-mod sub-command
The sh-to-mod sub-command is added to output as a modulefile content
the environment changes done by the evaluation of a shell script passed as
argument. sh-to-mod is especially useful for software providing a
shell script for their enablement in shell session: it can convert these
scripts into modulefiles.
Say for instance, a foo software has been installed and it provides a
foo-setup.sh script to activate foo software in user environment:
$ cat /path/to/foo-1.2/foo-setup.sh
#!/bin/sh
export FOOENV="$1"
export PATH=/path/to/foo-1.2/bin:$PATH
alias foo='foobin -q -l'
Calling module sh-to-mod on this shell script outputs the environment
changes it performs as a modulefile content:
$ module sh-to-mod sh /path/to/foo-1.2/foo-setup.sh arg1
#%Module
prepend-path PATH /path/to/foo-1.2/bin
set-alias foo {foobin -q -l}
setenv FOOENV arg1
Changes on environment variables, shell aliases, shell functions and current working directory are tracked. The following shells are supported: sh, dash, csh, tcsh, bash, ksh, ksh93, zsh and fish.
sh-to-mod acts as a full replacement for the standalone
createmodule.sh and createmodule.py scripts. However
those two scripts are currently still provided for compatibility purpose.
source-sh modulefile command
The source-sh modulefile command is introduced to source environment
changes done by the evaluation of a shell script passed as argument. With
newly introduced sh-to-mod sub-command resulting environment changes
done by script are output as modulefile commands. source-sh applies
those modulefile commands as if they were directly written in loading
modulefile.
source-sh is useful for software providing a shell script for their
enablement. If you want to enable such software with module yet
using shell script provided by software for this task, just write a modulefile
using source-sh command to call the shell script.
Keeping the same example used to describe sh-to-mod sub-command:
foo software provides a foo-setup.sh script for its activation. Create a
modulefile foo/1.2 that calls this script:
$ cat /path/to/modulefiles/foo/1.2
#%Module4.6
source-sh sh /path/to/foo-1.2/foo-setup.sh arg1
Displaying this modulefile indicates the environment changes done by script:
$ module display foo/1.2 ------------------------------------------------------------------- /path/to/modulefiles/foo/1.2: prepend-path PATH /path/to/foo-1.2/bin set-alias foo {foobin -q -l} setenv FOOENV arg1 -------------------------------------------------------------------
Loading the modulefile applies the environment changes seen above:
$ module load -v foo/1.2 Loading foo/1.2 $ echo $FOOENV arg1 $ alias foo alias foo='foobin -q -l'
Track of these changes is kept in user environment to be able to undo them when modulefile is unloaded:
$ module unload -v foo/1.2 Unloading foo/1.2 $ echo $FOOENV $ alias foo bash: alias: foo: not found
Changes on environment variables, shell aliases, shell functions and current working directory are tracked. The following shells are supported: sh, dash, csh, tcsh, bash, ksh, ksh93, zsh and fish.
Querying user's name and groups membership
Two new sub-commands are introduced for the module-info modulefile
command: username and usergroups. They respectively fetch the name of
the user currently running modulecmd.tcl or the name of all the groups
this user is member of.
These two new modulefile commands can help to adapt code to specific users or groups. Like for instance to instantiate a modulefile for each group the user is member of:
$ cat /path/to/modulefiles/foo/.modulerc #%Module4.6 foreach grp [module-info usergroups] { module-virtual foo/$grp .common } $ id -G -n grp1 grp2 grp3 $ module avail --------------- /path/to/modulefiles --------------- foo/grp1 foo/grp2 foo/grp3
username and usergroups sub-commands of module-info
modulefile command are only supported on Unix platform.
Hiding modules
The newly introduced module-hide modulefile command enables to
dynamically hide modulefiles, module aliases or symbolic versions specified to
it:
$ cat /path/to/modulefiles/bar/.modulerc #%Module4.6 module-version bar/1.0 old # hide 'old' symbolic version module-hide bar/old # hide all version 2 and above module-hide bar@2: $ cat /path/to/modulefiles/.modulerc #%Module4.6 # hide all versions of foo module module-hide foo
module-hide commands should be placed in module rc files and can
leverage the Advanced module version specifiers syntax as shown in the
above example.
Hidden modules are excluded from available module search or module selection unless query refers to hidden module by its exact name:
$ ml av --------------- /path/to/modulefiles --------------- bar/1.0 bar/2.0 $ module load -v foo ERROR: Unable to locate a modulefile for 'foo' $ module load -v foo/1.0 Loading foo/1.0 $ module avail bar/old --------------- /path/to/modulefiles --------------- bar/1.0(old)
module-hide command accepts a --soft option to apply a lighter of
hiding to modules:
$ cat /path/to/modulefiles/qux/.modulerc
#%Module4.6
# softly hide all qux modules
module-hide --soft qux
The soft hiding mode enables to hide modules from full availability listing yet keeping the ability to select such module for load without having to use module exact name:
$ ml av --------------- /path/to/modulefiles --------------- bar/1.0 bar/2.0 $ ml av qux --------------- /path/to/modulefiles --------------- qux/1.0 qux/2.0 $ module load -v qux Loading qux/2.0
Alternatively, a --hard option can be set on module-hide command
to ensure designated modules do not unveil even if referred by their exact
name:
$ cat /path/to/modulefiles/qux/.modulerc #%Module4.6 # softly hide all qux modules module-hide --soft qux # set highest version of qux hard hidden module-hide --hard qux/3.0 $ ml av qux/3.0 $ ml qux/3.0 ERROR: Unable to locate a modulefile for 'qux/3.0'
Some users or groups can be set unaffected by hiding mechanism with
the --not-user or --not-group options:
$ cat /path/to/modulefiles/quuz/.modulerc
#%Module4.6
# hiding does not apply to grp1 and grp2 groups
module-hide --not-group {grp1 grp2} quuz
$ id --groups --name grp1 grp7 $ ml av quuz --------------- /path/to/modulefiles --------------- quuz/1.0 quuz/2.0 $ ml -v quuz Loading quuz/2.0
Hiding mechanism can also be set effective only before or after a given date
time with the --before and --after options. Accepted date time format
is YYYY-MM-DD[THH:MM].
$ cat /path/to/modulefiles/fum/.modulerc
#%Module4.6
# hide only before a given date
module-hide --hard --before 2020-09-01T12:00 fum/1.0
# hide only after a given date
module-hide --hard --after 2020-09-01 fum/2.0
$ date Fri 04 Sep 2020 06:21:48 AM CEST $ ml av fum --------------- /path/to/modulefiles --------------- fum/1.0
Hidden modules can be included in available module searches if option
--all/-a is set on avail, aliases,
whatis or search sub-commands. Hard hidden modules are
unaffected by this option and stay hidden.
$ ml av -a --------------- /path/to/modulefiles --------------- bar/1.0(old) foo/1.0 fum/1.0 quuz/2.0 qux/2.0 bar/2.0 foo/2.0 quuz/1.0 qux/1.0
Forbidding use of modules
The module-forbid modulefile command is added to dynamically forbid
the evaluation of modulefiles it specifies. When forbidden, a module cannot be
loaded and an access error is returned when an attempt is made to evaluate it.
$ cat /path/to/modulefiles/foo/.modulerc #%Module4.6 module-forbid foo@1: $ ml foo/1.0 ERROR: Access to module 'foo/1.0' is denied $ ml No Modulefiles Currently Loaded.
module-forbid statements can be coupled with module-hide
statements to hide modules in addition to forbid their use.
module-forbid supports the --not-user, --not-group,
--before and --after options to still allow some users or forbid
modules before or after a given date time.
An additional error message can be defined with the --message option
to guide for instance users when they try to evaluate a forbidden module:
$ cat /path/to/modulefiles/bar/.modulerc #%Module4.6 module-forbid --message {Software bar/1.0 is decommissioned, please now use\ bar/2.0} --after 2020-09-01 bar/1.0 $ ml bar/1.0 ERROR: Access to module 'bar/1.0' is denied Software bar/1.0 is decommissioned, please now use bar/2.0
When an evaluated module will soon be forbidden, a message is returned to the
user to warn him/her of the near limit. An additional warning message can
also be defined here with the --nearly-message option to guide users.
$ cat /path/to/modulefiles/qux/.modulerc #%Module4.6 module-forbid --nearly-message {Version 1.0 will soon expire, please now use\ version 2.0} --after 2020-09-15 qux/1.0 $ date Tue 08 Sep 2020 06:49:43 AM CEST $ ml qux/1.0 Loading qux/1.0 WARNING: Access to module will be denied starting '2020-09-15' Version 1.0 will soon expire, please now use version 2.0
The range of time the nearly forbidden warning appears can be controlled
with the nearly_forbidden_days configuration option, whose value
equals to the number of days prior the module starts to be forbidden. This
configuration is set to 14 (days) by default and this value can be
controlled at configure time with
--with-nearly-forbidden-days option. When the
nearly_forbidden_days configuration is set through the
config sub-command, the MODULES_NEARLY_FORBIDDEN_DAYS
environment variable is set.
Tracing module execution
The trace verbosity is introduced between the verbose and debug
levels to report details on module searches, resolutions, selections and
evaluations. Trace mode can be enabled by setting the verbosity
config to the trace value or by using the -T/--trace
command-line switches.
To specifically render trace messages, the tr key is added to the color
palette with a default value of 2 (decreased intensity).
$ ml -T foo Evaluate modulerc: '/path/to/modulefiles/.modulerc' Get modules: {foo} matching 'foo' in '/path/to/modulefiles' Resolve: 'foo' into 'bar' Get modules: {bar bar/1.0} matching 'bar' in '/path/to/modulefiles' Select module: 'bar/1.0' (/path/to/modulefiles/bar/1.0) matching 'bar/1.0' Loading bar/1.0 Evaluate modulefile: '/path/to/modulefiles/bar/1.0' as 'bar/1.0'
v4.5
This new version is backward-compatible with previous version 4 releases. It fixes bugs but also introduces new functionalities that are described in this section. See the 4.5 release notes for a complete list of the changes between Modules v4.4 and v4.5.
ml command
The ml command is added to Modules. ml is a frontend to the module
command that reduces the number of characters to type to trigger module
actions.
With no argument provided ml is equivalent to module list, ml foo
corresponds to module load foo and ml -foo means module unload
foo:
$ ml foo $ ml Currently Loaded Modulefiles: 1) foo/2 $ ml -foo $ ml No Modulefiles Currently Loaded.
Multiple modules to either load or unload can be combined on a single command. The unloads are first processed then the loads.
ml accepts all command-line switches and sub-commands accepted by
module command:
$ ml avail -t foo
foo/1
foo/2
This handy interface has been originally developed by the Lmod project. Having this command line interface also supported on Modules helps to provide a similar user experience whatever the module implementation used.
JSON format output
The -j and --json command line switches are added for the avail,
list, savelist, whatis and search module sub-commands. When
set, the output result of these sub-commands is rendered in JSON format:
$ module avail --json bar | python -mjson.tool { "/path/to/modulefiles": { "bar/2.3": { "name": "bar/2.3", "pathname": "/path/to/modulefiles/bar/2.3", "symbols": [ "default" ], "type": "modulefile" }, "bar/3.4": { "name": "bar/3.4", "pathname": "/path/to/modulefiles/bar/3.4", "symbols": [], "type": "modulefile" } } } $ ml whatis -j foo/1.2.3 | python -mjson.tool { "/path/to/modulefiles": { "foo/1.2.3": { "name": "foo/1.2.3", "whatis": [ "The foo/1.2.3 modulefile" ] } } }
Improved Windows support
A new option to the ./configure script named
--enable-windows-support is introduced to install additional files
relative to the enablement of Modules on the Windows platform. When set, this
option installs module.cmd, ml.cmd and envml.cmd scripts in
bindir and initialization script cmd.cmd in initdir. With these
four files the Modules installation may be used from either a Unix or a
Windows platform.
module.cmd, ml.cmd and envml.cmd scripts respectively provide the
module, ml and envml commands for Windows cmd terminal shell,
relying on modulecmd.tcl script which was already able to produce shell
code for this Windows shell. Initialization script cmd.cmd adds the
directory of module.cmd, ml.cmd and envml.cmd to PATH.
These Windows-specific files are relocatable: module.cmd, ml.cmd and
envml.cmd scripts expect to find initialization script cmd.cmd in the
init directory next to them (to setup Modules-specific variables in
current environment) and cmd.cmd expects modulecmd.tcl to be found in
libexec directory and the 3 commands in bin directory next to it.
Starting from this 4.5 release a distribution zipball is published to
install Modules on Windows. This zip archive ships an install and an uninstall
scripts (INSTALL.bat and UNINSTALL.bat). The zipball can be built
locally from Modules sources by running make dist-win.
The Installing Modules on Windows document describes how to install Modules on Windows from the distribution zipball.
Error stack trace
Error messages will now embed a stack trace for unknown errors to help localize the root cause of issues. This change applies to modulefile evaluation:
Loading foo/1.2 Module ERROR: add-path cannot handle path equals to separator string while executing "append-path PATH :" (file "/path/to/modulefiles/foo/1.2" line 24) Please contact <root@localhost>
A stack trace is also returned when an unknown error occurs in
modulecmd.tcl script, which facilitates issue report and analysis:
$ module load bar ERROR: invalid command name "badcommand" while executing "badcommand" (procedure "module" line 14) invoked from within "module load bar" ("eval" body line 1) invoked from within "eval $execcmdlist" Please report this issue at https://github.com/cea-hpc/modules/issues
Automatic default and latest symbolic versions
When the implicit default mechanism and the Advanced module version
specifiers are both enabled, a default and a latest symbolic
versions are automatically defined for each module name.
This new feature gives the ability to select the highest version available for a module, without knowing beforehand this version name:
$ module load -v foo@latest Loading foo/1.10
The symbolic versions are automatically defined unless a symbolic version, an
alias or a regular module version already exists for these default or
latest version names.
v4.4
This new version is backward-compatible with previous version 4 releases. It fixes bugs but also introduces new functionalities that are described in this section. See the 4.4 release notes for a complete list of the changes between Modules v4.3 and v4.4.
Warning
Modules configuration option handling has been reworked
internally to provide a unified way for all options to get initialized,
retrieved or set. Existing site-specific configuration script should be
reviewed to make use of the new getConf, setConf, unsetConf
and lappendConf procedures to manipulate configuration options.
Specify modules in a case insensitive manner
The ability to match module name in a case insensitive manner has been added.
This feature can be enabled at different level with the following values set
to the icase configuration option:
never: a case sensitive match is applied in any casessearch: a case insensitive match is applied to theavail,whatisandpathssub-commandsalways: a case insensitive match is applied to search contexts and also to the other module sub-commands and modulefile Tcl commands for the module specification they receive as argument.
It can help for instance to load a module without knowing the case used to name its relative modulefile:
$ module config icase always $ module load -v mysoftware Loading MySoftware/1.0
Insensitive case match activation can be controlled at configure time with
the --with-icase option, which could be passed any of the above activation
levels. This option could be superseded with the MODULES_ICASE environment
variable, which could be set through the config sub-command with the
icase option. Command-line switch --icase supersedes in turns any
other icase configurations. When this command-line switch is passed, icase
mode equals always.
Extended default
The extended default mechanism has been introduced to help selecting a module
when only the first numbers in its version are specified. Starting portion of
the version, part separated from the rest of the version string by a .
character, could be used to refer to a more precise version number.
This mechanism is activated through the new configuration option
extended_default. It enables to refer to a module named foo/1.2.3 as
foo/1.2 or foo/1:
$ module config extended_default 1 $ module load -v foo/1 Loading foo/1.2.3
When multiple versions match partial version specified and only one module
should be selected, the default version (whether implicitly or explicitly
defined) among matches is returned. The following example shows that
foo/1.1.1, the foo module default version, is selected when it matches
query. Elsewhere the highest version (also called the latest version or the
implicit default) among matching modules is returned:
$ module av foo --------------- /path/to/modulefiles --------------- foo/1.1.1(default) foo/1.2.1 foo/1.10 foo/1.1.10 foo/1.2.3 $ module load -v foo/1.1 Loading foo/1.1.1 $ module purge $ module load -v foo/1.2 Loading foo/1.2.3 $ module purge $ module load -v foo/1 Loading foo/1.1.1
In case implicit_default option is disabled and no explicit default is
found among matches, an error is returned:
$ module config implicit_default 0 $ module load -v foo/1.2 ERROR: No default version defined for 'foo/1.2'
When it is enabled, extended default applies everywhere a module could be specified, which means it could be used with any module sub-command or any modulefile Tcl command receiving a module specification as argument. It may help for instance to declare dependencies between modules:
$ module show bar/3 ---------------------------------------------------------- /path/to/modulefiles/bar/3.4: prereq foo/1.2 ---------------------------------------------------------- $ module load --auto bar/3 Loading bar/3.4 Loading requirement: foo/1.2.3
Extended default activation can be controlled at configure time with the
--enable-extended-default option. This option could be superseded with the
MODULES_EXTENDED_DEFAULT environment variable, which could be set through
the config sub-command with the extended_default option.
Advanced module version specifiers
The ability to specify finer constraints on module version has been added to
Modules. It enables to filter the module selection to a given version list or
range by specifying after the module name a version constraint prefixed by the
@ character.
This new feature leverages the version specifier syntax of the Spack package manager as this syntax covers all the needs for a fine-grained selection of module versions. It copes very well with command-line typing, by avoiding characters having a special meaning on shells. Moreover the users of Spack that also are users of Modules may already be familiar with this syntax.
The mechanism introduced here is called advanced module version specifier
and it can be activated through the new configuration option
advanced_version_spec. Constraints can be expressed to refine the
selection of module version to:
a single version with the
@versionsyntax, for instancefoo@1.2.3syntax will select modulefoo/1.2.3a list of versions with the
@version1,version2,...syntax, for instancefoo@1.2.3,1.10will match modulesfoo/1.2.3andfoo/1.10a range of versions with the
@version1:,@:version2and@version1:version2syntaxes, for instancefoo@1.2:will select all versions of modulefoogreater than or equal to1.2,foo@:1.3will select all versions less than or equal to1.3andfoo@1.2:1.3matches all versions between1.2and1.3including1.2and1.3versions
This new feature enables for instance to list available versions of module
foo higher or equal to 1.2:
$ module config advanced_version_spec 1 $ module av foo --------------- /path/to/modulefiles --------------- foo/1.1.1(default) foo/1.2.1 foo/1.10 foo/1.1.10 foo/1.2.3 $ module av foo@1.2: --------------- /path/to/modulefiles --------------- foo/1.2.1 foo/1.2.3 foo/1.10
Then choose to load for instance a version higher than or equal to 1.2 and
less than or equal to 1.3. Default version is selected if it corresponds
to a version included in the range, elsewhere the highest version (also called
latest version or implicit default) is selected:
$ module load -v foo@1.2:1.3 Loading foo/1.2.3
In case implicit_default option is disabled and no explicit default is
found among version specifier matches, an error is returned:
$ module config implicit_default 0 $ module load -v foo@1.2:1.3 ERROR: No default version defined for 'foo@1.2:1.3'
When advanced module version specifier is enabled, it applies everywhere a module could be specified, which means it could be used with any module sub-command or any modulefile Tcl command receiving a module specification as argument. It may help for instance to declare smoother dependencies between modules:
$ module show bar@:2 ---------------------------------------------------------- /path/to/modulefiles/bar/2.3: prereq foo@1.1.10,1.2.1 ---------------------------------------------------------- $ module load --auto bar@:2 Loading bar/2.3 Loading requirement: foo/1.2.1
Advanced specification of single version or list of versions may benefit from the activation of the Extended default mechanism (range of versions natively handles abbreviated versions):
$ module config extended_default 1 $ module load -v foo@1.2 Loading foo/1.2.3 $ module unload -v foo @1.2,1.5 Unloading foo/1.2.3
Advanced module version specifier activation can be controlled at configure
time with the --enable-advanced-version-spec option. This option could be
superseded with the MODULES_ADVANCED_VERSION_SPEC environment variable,
which could be set through the config sub-command with the
advanced_version_spec option.
v4.3
This new version is backward-compatible with previous version 4 releases. It fixes bugs but also introduces new functionalities that are described in this section. See the 4.3 release notes for a complete list of the changes between Modules v4.2 and v4.3.
Modulepath rc file
A .modulerc file found at the root of an enabled modulepath directory is
now evaluated when modulepath is walked through to locate modulefiles. This
modulepath rc file gives for instance the ability to define module alias whose
name does not correspond to any module directory in this modulepath. Thus this
kind of module alias would not be found unless if it is defined at the
modulepath global scope.
Further I/O operations optimization
Additional work has been performed to save a significant number of filesystem I/O operations made to search and evaluate modulefiles.
When fully read, the content of a modulefile is now cached in memory to avoid new I/O operations in case this modulefile should be read one more time during the same module command evaluation.
Except for path, paths, list, avail and aliases module
commands always fully read a modulefile whether its full content is needed or
just its header to verify its validity. This way modulefiles are only read
once on commands that first check modulefile validity then read again valid
files to get their full content.
Last but not least, Modules Tcl extension library is introduced to extend the
Tcl language in order to provide more optimized I/O commands to read a file or
a directory content than native Tcl commands do. This library is built and
enabled in modulecmd.tcl script with --enable-libtclenvmodules
configure argument (it is enabled by default). As this library is written in
C, it must be compiled and --with-tcl or --with-tclinclude configure
arguments may be used to indicate where to find Tcl development files.
Modules Tcl extension library greatly reduces the number of filesystem I/O
operations by removing unneeded ioctl, fcntl and lstat system
calls done (by Tcl open command) to read each modulefile. Directory
content read is also improved by fetching hidden and regular files in one
pass. Moreover .modulerc and .version read access is tested only if
these files are found in the directory.
Colored output
The ability to graphically enhance some part of the produced output has been added to improve readability. Among others, error, warning and info message prefixes can be colored as well as modulepath, module alias and symbolic version.
Color mode can be set to never, auto or always. When color mode is
set to auto, output is colored only if the standard error output channel
is attached to a terminal.
Default color mode could be controlled at configure time with the
--enable-color and the --disable-color option, which respectively
correspond to the auto and never color mode. This default mode could
be superseded with the CLICOLOR, CLICOLOR_FORCE and MODULES_COLOR
environment variables and the --color command-line switch.
Color to apply to each element can be controlled with the MODULES_COLORS
environment variable or the --with-dark-background-colors and
--with-light-background-colors configure options. These variable and
options take as value a colon-separated list in the same fashion LS_COLORS
does. In this list, output item that should be highlighted is designated by
a key which is associated to a Select Graphic Rendition (SGR) code.
The MODULES_TERM_BACKGROUND environment variable and the
--with-terminal-background configure option help Modules to determine if
the color set for dark background or the color set for light background should
be used to color output in case no specific color set is defined with the
MODULES_COLORS variable.
Output items able to be colorized and their relative key are: highlighted
element (hi), debug information (db), tag separator (se); Error
(er), warning (wa), module error (me) and info (in) message
prefixes; Modulepath (mp), directory (di), module alias (al),
module symbolic version (sy), module default version (de) and
modulefile command (cm).
For instance the default color set for a terminal with dark background is defined to:
hi=1:db=2:se=2:er=91:wa=93:me=95:in=94:mp=1;94:di=94:al=96:sy=95:de=4:cm=92
When colored output is enabled and a specific graphical rendition is defined
for module default version, the default symbol is omitted and instead
the defined graphical rendition is applied to the relative modulefile. When
colored output is enabled and a specific graphical rendition is defined for
module alias, the @ symbol is omitted.
CLICOLOR and CLICOLOR_FORCE environment variables are also honored to
define color mode. The never mode is set if CLICOLOR equals to 0.
If CLICOLOR is set to another value, it corresponds to the auto mode.
The always mode is set if CLICOLOR_FORCE is set to a value different
than 0. Color mode set with these two variables is superseded by mode set
with MODULES_COLOR environment variable.
Configure modulecmd with config sub-command
The config sub-command has been added to module to help getting or
setting the modulecmd.tcl options. With no additional command-line
argument, this sub-command reports the current value of all existing options
with a mention to indicate if this value has been overridden from a
command-line switch or from an environment variable.
See the description of this sub-command in the module man page for a complete reference on existing configuration options.
Most of the options can be altered by passing the option name and a value to the sub-command. Setting an option by this mean overrides its default value, set at installation time in modulecmd.tcl script, by defining the environment variable which supersedes this default.:
$ module config auto_handling 1 $ module config auto_handling Modules Release 4.3.0 (2019-07-26) - Config. name ---------.- Value (set by if default overridden) --------------- auto_handling 1 (env-var)
Setting options with module config could be done in the Modules
initialization RC file to change default value of options when module
command is initialized.
When command-line switch --reset and an option name is passed to the
config sub-command, it restores default value for configuration option by
unsetting related environment variable.
With command-line switch --dump-state, the config sub-command reports,
in addition to currently set options, the current state of modulecmd.tcl
script and Modules-related environment variables. Providing the output of the
module config --dump-state command when submitting an issue to the Modules
project will help to analyze the situation.
Control module command verbosity
The ability to control message verbosity has been added so module command
can be configured whether it should display more or less information.
Available verbosity levels from the least to the most verbose are:
silent: turn off error, warning and informational messages but does not affect module command output result.concise: enable error and warning messages but disable informational messages.normal: turn on informational messages, like a report of the additional module evaluations triggered by loading or unloading modules, aborted evaluation issues or a report of each module evaluation occurring during a restore or source sub-commands.verbose: add additional informational messages, like a systematic report of the loading or unloading module evaluations.debug: print debugging messages about module command execution.
Default verbosity level can be controlled at configure time with the
--with-verbosity option, which could be passed any of the above level
names. This default verbosity level could be superseded with the
MODULES_VERBOSITY environment variable, which could be set through the
config sub-command with the verbosity option. Command-line switches
--silent, --verbose and --debug supersede in turns any other
verbosity configuration to respectively set module command silent, verbose or
in debug mode.
Other new sub-commands, command-line switches and environment variables
The avail sub-command gets two new command-line switches: --indepth and --no-indepth. These options control whether search results should recursively include or not modulefiles from directories matching search query. Shell completion scripts have been updated to complete available modulefiles in the no in depth mode.
The MODULES_AVAIL_INDEPTH environment variable defines if the avail sub-command should include or exclude by default the modulefiles from directories matching search query. Its value is superseded by the use of the --indepth and --no-indepth command-line switches.
The clear sub-command, which was available on Modules version 3.2, has been reintroduced. This sub-command resets the Modules runtime information but does not apply further changes to the environment at all. This sub-command now leverages the --force command-line switch to skip its confirmation dialog.
The MODULES_SITECONFIG environment variable defines an additional siteconfig script which is loaded if it exists after the siteconfig script configured at build time in
modulecmd.tcl. This ability is enabled by default and could be disabled with configure option--with-locked-configs=extra_siteconfig.The MODULES_UNLOAD_MATCH_ORDER environment variable sets whether the firstly or the lastly loaded module should be selected for unload when multiple loaded modules match unload request. Configure option
--with-unload-match-orderdefines this setting which can be superseded by the environment variable. By default, lastly loaded module is selected and it is recommended to keep this behavior when used modulefiles express dependencies between each other.The MODULES_IMPLICIT_DEFAULT environment variable sets whether an implicit default version should be defined for modules with no default version explicitly defined. When enabled, which is the default behavior, a module version is automatically selected (latest one) when the generic name of the module is passed. When implicit default is disabled and no default version is explicitly defined for a module, the name of this module to evaluate should be fully qualified elsewhere an error is returned. Configure option
--enable-implicit-defaultdefines this setting which can be superseded by the environment variable. This superseding mechanism can be disabled with configure option--with-locked-configs=implicit_default.The MODULES_SEARCH_MATCH environment variable defines the matching style to perform when searching for available modules. With starts_with value, modules whose name begins by search query string are returned. When search match style is set to contains, modules returned are those whose fully qualified name contains search query string. Configure option
--with-search-matchdefines this setting which can be superseded by the environment variable, which in turns can be superseded by the --starts-with and --contains command-line switches of avail module sub-command.The MODULES_SET_SHELL_STARTUP environment variable controls whether or not shell startup file should be set to ensure
modulecommand is defined once shell has been initialized. When enabled, theENVandBASH_ENVenvironment variables are set, whenmodulefunction is defined, to the Modules bourne shell initialization script. Configure options--enable-set-shell-startupand--disable-set-shell-startupdefine this setting which can be superseded by the environment variable.When initializing the
modulecommand in a shell session, initialization configuration files stored in the defined configuration directory are taken into account if present instead of the configuration files stored in the initialization script directory. When they are stored in the configuration directory, these configuration files are namedinitrcandmodulespathinstead of respectivelymodulercand.modulespath. The location of the installation of those files can be controlled with configure option--with-initconf-in, which acceptsetcdirandinitdirvalues.The MODULES_WA_277 environment variable helps to define an alternative
modulealias on Tcsh shell when set to 1. It workarounds an issue on Tcsh history mechanism occurring with defaultmodulecommand alias: erroneous history entries are recorded each time themodulecommand is called. However the alternative definition of the module alias weakens shell evaluation of the code produced by modulefiles. Characters with special meaning for Tcsh shell (like { and }) may not be used anymore in shell alias definition elsewhere the evaluation of the code produced by modulefiles will return a syntax error.
v4.2
This new version is backward-compatible with previous version 4 releases. It fixes bugs but also introduces new functionalities that are described in this section. See the 4.2 release notes for a complete list of the changes between Modules v4.1 and v4.2.
Modulefile conflict constraints consistency
With the conflict modulefile command, a given modulefile can list the other modulefiles it conflicts with. To load this modulefile, the modulefiles it conflicts with cannot be loaded.
This constraint was until now satisfied when loading the modulefile declaring
the conflict but it vanished as soon as this modulefile was loaded. In the
following example a modulefile declares a conflict with b:
$ module load b a WARNING: a cannot be loaded due to a conflict. HINT: Might try "module unload b" first. $ module list Currently Loaded Modulefiles: 1) b $ module purge $ module load a b $ module list Currently Loaded Modulefiles: 1) a 2) b
Consistency of the declared conflict is now ensured to satisfy this
constraint even after the load of the modulefile declaring it. This is
achieved by keeping track of the conflict constraints of the loaded
modulefiles in an environment variable called MODULES_LMCONFLICT:
$ module load a b ERROR: WARNING: b cannot be loaded due to a conflict. HINT: Might try "module unload a" first. $ module list Currently Loaded Modulefiles: 1) a
An environment variable is used to keep track of this conflict information to
proceed the same way than used to keep track of the loaded modulefiles with
the LOADEDMODULES environment variable.
In case a conflict constraint toward a modulefile is set by an already loaded modulefile, loading the conflicting modulefile will lead to a load evaluation attempt in order for this modulefile to get the chance to solve the constraint violation. If at the end of the load evaluation, the conflict has not been solved, modulefile load will be discarded.
Warning
On versions 4.2.0 and 4.2.1, a conflict constraint set by
an already loaded modulefile forbade the load of the conflicting
modulefile. This has been changed starting version 4.2.2 to better cope
with behaviors of previous Modules version: an evaluation attempt of the
conflicting modulefile is made to give it the opportunity to solve this
conflict by using module unload modulefile command.
Modulefile prereq constraints consistency
With the prereq modulefile command, a given modulefile can list the other modulefiles it pre-requires. To load this modulefile, the modulefiles it pre-requires must be loaded prior its own load.
This constraint was until now satisfied when loading the modulefile declaring
the prereq but, as for the declared conflict, it vanished as soon as
this modulefile was loaded. In the following example c modulefile declares
a prereq on a:
$ module load c WARNING: c cannot be loaded due to missing prereq. HINT: the following module must be loaded first: a $ module list No Modulefiles Currently Loaded. $ module load a c $ module list Currently Loaded Modulefiles: 1) a 2) c $ module unload a $ module list Currently Loaded Modulefiles: 1) c
Consistency of the declared prereq is now ensured to satisfy this
constraint even after the load of the modulefile declaring it. This is
achieved, like for the conflict consistency, by keeping track of the prereq
constraints of the loaded modulefiles in an environment variable called
MODULES_LMPREREQ:
$ module load a c $ module list Currently Loaded Modulefiles: 1) a 2) c $ module unload a ERROR: WARNING: a cannot be unloaded due to a prereq. HINT: Might try "module unload c" first. $ module list Currently Loaded Modulefiles: 1) a 2) c
By-passing module defined constraints
The ability to by-pass a conflict or a prereq constraint defined by
modulefiles is introduced with the --force command line switch (-f for
short notation) for the load, unload and switch sub-commands.
With this new command line switch, a given modulefile is loaded even if it
conflicts with other loaded modulefiles or even if the modulefiles it
pre-requires are not loaded. Some example reusing the same modulefiles a,
b and c than above:
$ module load b $ module load --force a WARNING: a conflicts with b $ module list Currently Loaded Modulefiles: 1) b 2) a $ module purge $ module load --force c WARNING: c requires a loaded $ module list Currently Loaded Modulefiles: 1) c
--force also enables to unload a modulefile required by another loaded
modulefiles:
$ module load a c $ module list Currently Loaded Modulefiles: 1) a 2) c $ module unload --force a WARNING: a is required by c $ module list Currently Loaded Modulefiles: 1) c
In a situation where some of the loaded modulefiles have unsatisfied constraints corresponding to the prereq and conflict they declare, the save and reload sub-commands do not perform and return an error.
Automated module handling mode
An automatic management of the dependencies between modulefiles has been added and it is called automated module handling mode. This new mode consists in additional actions triggered when loading or unloading a modulefile to satisfy the constraints it declares.
When loading a modulefile, following actions are triggered:
Requirement Load (ReqLo): load of the modulefiles declared as a prereq of the loading modulefile.
Dependent Reload (DepRe): reload of the modulefiles declaring a prereq onto loaded modulefile or declaring a prereq onto a modulefile part of this reloading batch.
When unloading a modulefile, following actions are triggered:
Dependent Unload (DepUn): unload of the modulefiles declaring a non-optional prereq onto unloaded modulefile or declaring a non-optional prereq onto a modulefile part of this unloading batch. A prereq modulefile is considered optional if the prereq definition order is made of multiple modulefiles and at least one alternative modulefile is loaded.
Useless Requirement Unload (UReqUn): unload of the prereq modulefiles that have been automatically loaded for either the unloaded modulefile, an unloaded dependent modulefile or a modulefile part of this useless requirement unloading batch. Modulefiles are added to this unloading batch only if they are not required by any other loaded modulefiles.
MODULES_LMNOTUASKEDenvironment variable helps to keep track of these automatically loaded modulefiles and to distinguish them from modulefiles asked by user.Dependent Reload (DepRe): reload of the modulefiles declaring a conflict or an optional prereq onto either the unloaded modulefile, an unloaded dependent or an unloaded useless requirement or declaring a prereq onto a modulefile part of this reloading batch.
In case a loaded modulefile has some of its declared constraints unsatisfied (pre-required modulefile not loaded or conflicting modulefile loaded for instance), this loaded modulefile is excluded from the automatic reload actions described above.
For the specific case of the switch sub-command, where a modulefile is unloaded to then load another modulefile. Dependent modulefiles to Unload are merged into the Dependent modulefiles to Reload that are reloaded after the load of the switched-to modulefile.
This automated module handling mode integrates concepts (like the Dependent Reload mechanism) of the Flavours extension, which was designed for Modules compatibility version. As a whole, automated module handling mode can be seen as a generalization and as an expansion of the Flavours concepts.
This new feature can be controlled at build time with the
--enable-auto-handling configure option. This default configuration can be
superseded at run-time with the MODULES_AUTO_HANDLING environment variable
or the command line switches --auto and --no-auto.
By default, automated module handling mode is disabled and will stay so until the next major release version (5.0) where it will be enabled by default. This new feature is currently considered experimental and the set of triggered actions will be refined over the next feature releases.
Consistency of module load/unload commands in modulefile
With the module load modulefile command, a given modulefile can automatically load a modulefile it pre-requires. Similarly with the module unload modulefile command, a given modulefile can automatically unload a modulefile it conflicts with.
Both commands imply additional actions on the loaded environment (loading or unloading extra modulefiles) that should cope with the constraints defined by the loaded environment.
Additionally module load and module unload modulefile commands express themselves constraints on loaded environment that should stay satisfied to ensure consistency.
To ensure the consistency of module load modulefile command once the
modulefile defining it has been loaded, this command is assimilated to a
prereq command. Thus the defined constraint is recorded in the
MODULES_LMPREREQ environment variable. Same approach is used for module
unload modulefile command which is assimilated to a conflict command.
Thus the defined constraint is recorded in the MODULES_LMCONFLICT
environment variable.
To ensure the consistency of the loaded environment, the additional actions of the module load and module unload modulefile commands have been adapted in particular situations:
When unloading modulefile, module load command will unload the modulefile it targets only if no other loaded modulefile requires it and if this target has not been explicitly loaded by user.
When unloading modulefile, module unload command does nothing as the relative conflict registered at load time ensure environment consistency and will forbid conflicting modulefile load.
Please note that loading and unloading results may differ than from previous Modules version now that consistency is checked:
Modulefile targeted by a module load modulefile command may not be able to load due to a registered conflict in the currently loaded environment. Which in turn will break the load of the modulefile declaring the module load command.
Modulefile targeted by a module unload modulefile command may not be able to unload due to a registered prereq in the loaded environment. Which in turn will break the load of the modulefile declaring the module unload command.
If automated module handling mode is enabled, module load modulefile command is interpreted when unloading modulefile as part of the Useless Requirement Unload (UReqUn) mechanism not through modulefile evaluation. As a consequence, an error occurring when unloading the modulefile targeted by the module load command does not break the unload of the modulefile declaring this command. Moreover unload of the module load targets is done in the reverse loaded order, not in the module load command definition order.
Modulefile alias and symbolic modulefile name consistency
With the module-alias and module-version modulefile commands, alternative names can be given to a modulefile. When these names are used to load for instance a modulefile, they are resolved to the modulefile they target which is then processed for the load action.
Until now, the alias and symbolic version names were correctly resolved for
the load and unload actions and also for the querying sub-commands
(like avail or whatis). However this alternative name information
vanishes once the modulefile it resolves to is loaded. As a consequence there
was no consistency over these alternative designations. In the following
example f modulefile declares a conflict on e alias which resolves to
d modulefile:
$ module load e $ module list Currently Loaded Modulefiles: 1) d $ module info-loaded e $ module load f $ module list Currently Loaded Modulefiles: 1) d 2) f
Consistency of the alternative names set on a modulefile with module-alias
and module-version commands is now ensured to enable modulefile commands
prereq, conflict, is-loaded and module-info loaded using these
alternative designations as argument. This consistency is achieved, like for
the conflict and prereq consistencies, by keeping track of the alternative
names of the loaded modulefiles in an environment variable called
MODULES_LMALTNAME:
$ module load e $ module list Currently Loaded Modulefiles: 1) d $ module info-loaded e d $ module load f WARNING: f cannot be loaded due to a conflict. HINT: Might try "module unload e" first. $ module list Currently Loaded Modulefiles: 1) d
Environment variable change through modulefile evaluation context
All environment variable edition commands (setenv, unsetenv,
append-path, prepend-path and remove-path) have been updated to:
Reflect environment variable value change on the environment of the current modulefile Tcl interpreter. So using
$env(VAR)will return the currently defined value for environment variableVAR, not the one found prior modulefile evaluation.Clear environment variable content instead of unsetting it on the environment of the current modulefile Tcl interpreter to avoid raising error about accessing an undefined element in
$env(). Code is still produced to purely unset environment variable in shell environment.
Exception is made for the whatis evaluation mode: environment variables
targeted by variable edition commands are not set to the defined value in the
evaluation context during this whatis evaluation. These variables are
only initialized to an empty value if undefined. This exception is made to
save performances on this global evaluation mode.
Improved module message report
Module sub-commands like load, unload or switch, may perform
multiple load or unload modulefile evaluations in a row. Also these kind of
evaluation modes may sometimes trigger additional load or unload evaluations,
when for instance a modulefile contains a module load command.
To improve the readability of the module messages produced relatively to a load or an unload evaluation, these messages are now stacked under a Loading or an Unloading message block that gathers all the messages produced for a given modulefile evaluation:
$ module load --no-auto foo
Loading foo/1.2
ERROR: foo/1.2 cannot be loaded due to missing prereq.
HINT: the following module must be loaded first: bar/4.5
In addition, foreground load, unload, switch and restore
actions (i.e., asked on the command-line) now report a summary of the
additional load and unload evaluations that were eventually triggered in
the process:
$ module load --auto foo
Loading foo/1.2
Loading requirement: bar/4.5
New modulefile commands
2 new modulefile Tcl commands have been introduced:
set-function: define a shell function on sh-kind and fish shells.
unset-function: unset a shell function on sh-kind and fish shells.
v4.1
This new version is backward-compatible with previous version 4 releases. It fixes bugs but also introduces new functionalities that are described in this section. See the 4.1 release notes for a complete list of the changes between Modules v4.0 and v4.1.
Virtual modules
A virtual module stands for a module name associated to a modulefile. The modulefile is the script interpreted when loading or unloading the virtual module which appears or can be found with its virtual name.
The module-virtual modulefile command is introduced to give the ability to define these virtual modules. This new command takes a module name as first argument and a modulefile location as second argument:
module-virtual app/1.2.3 /path/to/virtualmod/app
With this feature it is now possible to dynamically define modulefiles depending on the context.
Extend module command with site-specific Tcl code
module command can now be extended with site-specific Tcl
code. modulecmd.tcl now looks at a siteconfig.tcl file in an
etcdir defined at configure time (by default $prefix/etc). If
it finds this Tcl script file, it is sourced within modulecmd.tcl at the
beginning of the main procedure code.
siteconfig.tcl enables to supersede any global variable or procedure
definitions made in modulecmd.tcl with site-specific code. A module
sub-command can for instance be redefined to make it fit local needs
without having to touch the main modulecmd.tcl.
Quarantine mechanism to protect module execution
To protect the module command run-time environment from side effect
coming from the current environment definition a quarantine mechanism
is introduced. This mechanism, sets within module function definition
and shell initialization script, modifies the modulecmd.tcl run-time
environment to sanitize it.
The mechanism is piloted by environment variables. First of all
MODULES_RUN_QUARANTINE, a space-separated list of environment variable
names. Every variable found in MODULES_RUN_QUARANTINE will be set in
quarantine during the modulecmd.tcl run-time. Their value will be set
empty or set to the value of the corresponding MODULES_RUNENV_<VAR>
environment variable if defined. Once modulecmd.tcl is started it
restores quarantine variables to their original values.
MODULES_RUN_QUARANTINE and MODULES_RUNENV_<VAR> environment variables
can be defined at build time by using the following configure option:
--with-quarantine-vars='VARNAME[=VALUE] ...'
Quarantine mechanism is available for all supported shells except csh
and tcsh.
Pager support
The informational messages Modules sends on the stderr channel may sometimes be quite long. This is especially the case for the avail sub-command when hundreds of modulefiles are handled. To improve the readability of those messages, stderr output can now be piped into a paging command.
This new feature can be controlled at build time with the --with-pager
and --with-pager-opts configure options. Default pager command is set
to less and its relative options are by default -eFKRX. Default
configuration can be supersedes at run-time with MODULES_PAGER environment
variables or command-line switches (--no-pager, --paginate).
Warning
On version 4.1.0, the PAGER environment variable was
taken in consideration to supersede pager configuration at run-time. Since
version 4.1.1, PAGER environment variable is ignored to avoid side
effects coming from the system general pager configuration.
Module function to return value in scripting languages
On Tcl, Perl, Python, Ruby, CMake and R scripting shells, module function was not returning value and until now an occurred error led to raising a fatal exception.
To make module function more friendly to use on these scripting shells
it now returns a value. False in case of error, true if everything goes well.
As a consequence, returned value of a module sub-command can be checked. For instance in Python:
if module('load', 'foo'):
# success
else:
# failure
New modulefile commands
4 new modulefile Tcl commands have been introduced:
is-saved: returns true or false whether a collection, corresponding to currently set collection target, exists or not.
is-used: returns true or false whether a given directory is currently enabled in
MODULEPATH.is-avail: returns true or false whether a given modulefile exists in currently enabled module paths.
module-info loaded: returns the exact name of the modulefile currently loaded corresponding to the name argument.
Multiple collections, paths or modulefiles can be passed respectively to
is-saved, is-used and is-avail in which case true is returned if
at least one argument matches condition (acts as a OR boolean operation). No
argument may be passed to is-loaded, is-saved and is-used
commands to return if anything is respectively loaded, saved or used.
If no loaded modulefile matches the module-info loaded query, an empty
string is returned.
New module sub-commands
Modulefile-specific commands are sometimes wished to be used outside of a modulefile context. Especially for the commands managing path variables or commands querying current environment context. So the following modulefile-specific commands have been made reachable as module sub-commands with same arguments and properties as if called from within a modulefile:
append-path
prepend-path
remove-path
is-loaded
info-loaded
The is-loaded sub-command returns a boolean value. Small Python example:
if module('is-loaded', 'app'):
print 'app is loaded'
else:
print 'app not loaded'
info-loaded returns a string value and is the sub-command counterpart
of the module-info loaded modulefile command:
$ module load app/0.8 $ module info-loaded app app/0.8
v4.0
Major evolution occurs with this v4.0 release as the traditional module command implemented in C is replaced by the native Tcl version. This full Tcl rewrite of the Modules package was started in 2002 and has now reached maturity to take over the binary version. This flavor change enables to refine and push forward the module concept.
This document provides an outlook of what is changing when migrating from v3.2 to v4.0 by first describing the introduced new features. Both v3.2 and v4.0 are quite similar and transition to the new major version should be smooth. Slights differences may be noticed in a few use-cases. So the second part of the document will help to learn about them by listing the features that have been discontinued in this new major release or the features where a behavior change can be noticed.
New features
On its overall this major release brings a lot more robustness to the module command with now more than 4000 non-regression tests crafted to ensure correct operations over the time. This version 4.0 also comes with fair amount of improved functionalities. The major new features are described in this section.
Additional shells supported
Modules v4 introduces support for fish, lisp, tcl and R code output.
Non-zero exit code in case of error
All module sub-commands will now return a non-zero exit code in case of error whereas Modules v3.2 always returned zero exit code even if issue occurred.
Output redirect
Traditionally the module command output text that should be seen by the user on stderr since shell commands are output to stdout to change shell's environment. Now on sh, bash, ksh, zsh and fish shells, output text is redirected to stdout after shell command evaluation if shell is in interactive mode.
Filtering avail output
Results obtained from the avail sub-command can now be filtered to only get the default version of each module name with use of the --default or -d command line switch. Default version is either the explicitly set default version or the highest numerically sorted modulefile or module alias if no default version set.
It is also possible to filter results to only get the highest numerically sorted version of each module name with use of the --latest or -L command line switch.
Extended support for module alias and symbolic version
Module aliases are now included in the result of the avail, whatis
and apropos sub-commands. They are displayed in the module path
section where they are defined or in a global/user modulerc section for
aliases set in user's or global modulerc file. A @ symbol is added
in parenthesis next to their name to distinguish them from modulefiles.
Search may be performed with an alias or a symbolic version-name passed as argument on avail, whatis and apropos sub-commands.
Modules v4 resolves module alias or symbolic version passed to unload command to then remove the loaded modulefile pointed by the mentioned alias or symbolic version.
A symbolic version sets on a module alias is now propagated toward the resolution path to also apply to the relative modulefile if it still correspond to the same module name.
Hiding modulefiles
Visibility of modulefiles can be adapted by use of file mode bits or file ownership. If a modulefile should only be used by a given subset of persons, its mode an ownership can be tailored to provide read rights to this group of people only. In this situation, module only reports the modulefile, during an avail command for instance, if this modulefile can be read by the current user.
These hidden modulefiles are simply ignored when walking through the modulepath content. Access issues (permission denied) occur only when trying to access directly a hidden modulefile or when accessing a symbol or an alias targeting a hidden modulefile.
Improved modulefiles location
When looking for an implicit default in a modulefile directory, aliases are now taken into account in addition to modulefiles and directories to determine the highest numerically sorted element.
Modules v4 resolves module alias or symbolic version when it points to a modulefile located in another modulepath.
Access issues (permission denied) are now distinguished from find issues
(cannot locate) when trying to access directly a directory or a modulefile
as done on load, display or whatis commands. In addition,
on this kind of access not readable .modulerc or .version files are
ignored rather producing a missing magic cookie error.
Module collection
Modules v4 introduces support for module collections. Collections describe a sequence of module use then module load commands that are interpreted by Modules to set the user environment as described by this sequence. When a collection is activated, with the restore sub-command, modulepaths and loaded modules are unused or unloaded if they are not part or if they are not ordered the same way as in the collection.
Collections are generated by the save sub-command that dumps the current
user environment state in terms of modulepaths and loaded modules. By default
collections are saved under the $HOME/.module directory. Collections
can be listed with savelist sub-command, displayed with saveshow
and removed with saverm.
Collections may be valid for a given target if they are suffixed. In this
case these collections can only be restored if their suffix correspond
to the current value of the MODULES_COLLECTION_TARGET environment
variable. Saving collection registers the target footprint by suffixing
the collection filename with .$MODULES_COLLECTION_TARGET.
Path variable element counter
Modules 4 provides path element counting feature which increases a reference counter each time a given path entry is added to a given path-like environment variable. As consequence a path entry element is removed from a path-like variable only if the related element counter is equal to 1. If this counter is greater than 1, path element is kept in variable and reference counter is decreased by 1.
This feature allows shared usage of particular path elements. For instance,
modulefiles can append /usr/local/bin to PATH, which is not unloaded
until all the modulefiles that loaded it unload too.
Optimized I/O operations
Substantial work has been done to reduce the number of I/O operations
done during global modulefile analysis commands like avail or
whatis. stat, open, read and close I/O operations have
been cut down to the minimum required when walking through the modulepath
directories to check if files are modulefiles or to resolve module aliases.
Interpretation of modulefiles and modulerc are handled by the minimum required Tcl interpreters. Which means a configured Tcl interpreter is reused as much as possible between each modulefile interpretation or between each modulerc interpretation.
Sourcing modulefiles
Modules 4 introduces the possibility to source a modulefile rather loading it. When it is sourced, a modulefile is interpreted into the shell environment but then it is not marked loaded in shell environment which differ from load sub-command.
This functionality is used in shell initialization scripts once module
function is defined. There the etc/modulerc modulefile is sourced to
setup the initial state of the environment, composed of module use
and module load commands.
Removed features and substantial behavior changes
Following sections provide list of Modules v3.2 features that are discontinued on Modules v4 or features with a substantial behavior change that should be taken in consideration when migrating to v4.
Package initialization
MODULESBEGINENV environment snapshot functionality is not supported
anymore on Modules v4. Modules collection mechanism should be used instead to
save and restore sets of enabled modulepaths and loaded modulefiles.
Command line switches
Some command line switches are not supported anymore on v4.0. When still using them, a warning message is displayed and the command is ran with these unsupported switches ignored. Following command line switches are concerned:
--force,-f--human--verbose,-v--silent,-s--create,-c--icase,-i--userlvllvl,-ulvl
Module sub-commands
During an help sub-command, Modules v4 does not redirect output made on stdout in ModulesHelp Tcl procedure to stderr. Moreover when running help, version 4 interprets all the content of the modulefile, then call the ModulesHelp procedure if it exists, whereas Modules 3.2 only interprets the ModulesHelp procedure and not the rest of the modulefile content.
When load is asked on an already loaded modulefiles, Modules v4 ignores this new load order whereas v3.2 refreshed shell alias definitions found in this modulefile.
When switching on version 4 an old modulefile by a new one, no error is raised if old modulefile is not currently loaded. In this situation v3.2 threw an error and abort switch action. Additionally on switch sub-command, new modulefile does not keep the position held by old modulefile in loaded modules list on Modules v4 as it was the case on v3.2. Same goes for path-like environment variables: replaced path component is appended to the end or prepended to the beginning of the relative path-like variable, not appended or prepended relatively to the position hold by the swapped path component.
During a switch command, version 4 interprets the swapped-out modulefile
in unload mode, so the sub-modulefiles loaded, with module load
order in the swapped-out modulefile are also unloaded during the switch.
Modules 4 provides path element counting feature which increases a reference
counter each time a given path entry is added to a given environment
variable. This feature also applies to the MODULEPATH environment
variable. As consequence a modulepath entry element is removed from the
modulepath enabled list only if the related element counter is equal to 1.
When unusing a modulepath if its reference counter is greater than 1,
modulepath is kept enabled and reference counter is decreased by 1.
On Modules 3.2 paths composing the MODULEPATH environment variable
may contain reference to environment variable. These variable references
are resolved dynamically when MODULEPATH is looked at during module
sub-command action. This feature has been discontinued on Modules v4.
Following Modules sub-commands are not supported anymore on v4.0:
clearupdate
Modules specific Tcl commands
Modules v4 provides path element counting feature which increases a reference
counter each time a given path entry is added to a given environment
variable. As a consequence a path entry element is not always removed
from a path-like variable when calling to remove-path or calling to
append-path or append-path at unloading time. The path element is
removed only if its related element counter is equal to 1. If this counter
is greater than 1, path element is kept in variable and reference counter
is decreased by 1.
On Modules v4, module-info mode returns during an unload sub-command
the unload value instead of remove on Modules v3.2. However if mode
is tested against remove value, true will be returned. During a switch
sub-command on Modules v4, unload then load is returned instead of
switch1 then switch2 then switch3 on Modules v3.2. However if
mode is tested against switch value, true will be returned.
When using set-alias, Modules v3.2 defines a shell function when variables are in use in alias value on Bourne shell derivatives, Modules 4 always defines a shell alias never a shell function.
Some Modules specific Tcl commands are not supported anymore on v4.0. When still using them, a warning message is displayed and these unsupported Tcl commands are ignored. Following Modules specific Tcl commands are concerned:
module-info flagsmodule-info tracemodule-info tracepatmodule-info usermodule-logmodule-tracemodule-usermodule-verbosity
Further reading
To get a complete list of the differences between Modules v3.2 and v4, please read the Changes between versions document.
A significant number of issues reported for v3.2 have been closed on v4. List of these closed issues can be found at: