13  Creating Modulefiles

13.1 Sample module file

#%Module1.0####################################################################

proc ModulesHelp { } {
    global _module_name

    puts stderr "The $_module_name modulefile defines the default system paths and"
    puts stderr "environment variables needed to use the $_module_name libraries and tools."
    puts stderr ""
}

set _module_name    [module-info name]

## Change to be user-specifc path
set approot /projects/stat/shared/$::env(USER)/software/libevent/2.1.11

module-whatis "       Name: libevent"
module-whatis "  Long name: libevent - An event notification library"
module-whatis "    Version: 2.1.11"
module-whatis "   Category: library"
module-whatis "Description: An event notification library"
module-whatis "        URL: https://libevent.org/"
module-whatis ""

if { [ is-loaded gcc/7.2.0 ] } {} else { module load gcc/7.2.0 }

prepend-path    PATH        $approot
prepend-path    LD_LIBRARY_PATH     $approot/lib
prepend-path    LD_RUN_PATH         $approot/lib
prepend-path    MANPATH         $approot/man
prepend-path --delim " " LDFLAGS "-L $approot/lib"
prepend-path --delim " " CPPFLAGS "-I $approot/include"
prepend-path --delim " " CFLAGS "-I $approot/include"

• prepend-path by itself is for variables like PATH LD_LIBRARY_PATH, LD_RUN_PATH, LIBRARY_PATH, CPATH, MANPATH …
• prepend-path --delim " " is for compiler flag variables like LDFLAGS, CPPFLAGS, CFLAGS, …
• Module dependencies should be specified with:

## Load module if not already loaded.
if { [ is-loaded <module> ] } {} else { module load <module> }

• conflict <module> emphasizes any modules that can’t be loaded together

14 Self-notes

• $::env() is part of TCL language and allows the TCL script/modulefile to access variables found in the env array.
  • $::env(HOME) would return: /home/$USER
  • $::env(USER) would return: $USER
  • Details: https://wiki.tcl-lang.org/page/env

Useful references:

https://cea-hpc.github.io/modules/docs/MC2_whitney_paper.pdf https://www.acrc.bris.ac.uk/acrc/pdf/customising-environment-variables.pdf