Log module command

It is sometimes desired to better understand the module usage on the system we manage. Especially to determine what are the modulefiles most used and what are those never used that could be removed. This recipe describes a way to track the module usage by logging each request made.


Logging module commands is implemented by the use of a site-specific configuration that supersedes the definition of the module command to execute the logger command, in order to send a message to the system log, prior processing the module command itself. The log message sent describes the module command called and who called it.

# override 'module' procedure to log each call made by user
rename ::module ::__module
proc module {command args} {
   if {[getEvalModuleStackDepth] == 0} {
      exec logger -t module "[get-env USER]: $command [join $args]"
   return [eval __module "{$command}" $args]

Compatible with Modules v4.2+


Create site-specific configuration directory if it does not exist yet:

$ mkdir /usr/share/Modules/etc

Then copy there the site-specific configuration script of this recipe:

$ cp example/log-module-commands/siteconfig.tcl /usr/share/Modules/etc/


Defined location for the site-specific configuration script may vary from one installation to another. To determine the expected location for this file on your setup, check the value of the siteconfig option on Modules version 4.3 or above:

$ module config siteconfig

On older version of Modules, check the modulecmd.tcl script:

$ grep '^set g_siteconfig ' $MODULES_CMD

Usage example

Loading a bare modulefile:

$ module load example

A log entry can then be retrieved from system log files:

$ journalctl -q -t module -n 1
Sep 12 20:24:01 hostname module[9925]: username: load example