New Features in Lmod
====================

**Updated Tracking Module Usage**
  (Lmod 8.7.54+) The optional module usage tracking system has been
  updated.  It now uses Python3 and mysql.connector.python.  The new
  system also greatly reduces the amount of data stored.  See the
  updated documentation at :ref:`tracking_usage` and how to convert
  from old gen 1 format to the new gen 2 database format at
  :ref:`convert_gen1_gen2-label` 


**LMOD_SHOW_HIDDEN**
  (Lmod 8.7.54+) The environment variable **LMOD_SHOW_HIDDEN**
  can be used to control whether hidden modules will be show under
  list, spider, avail.  See :ref:`show_hidden-label` for more details


**Accessing isVisible status from load hook**
   (Lmod 8.7.52+) The mname object is passed to the load hook.  Sites
   can access the isVisible status by t.mname:isVisible()

**hide** {} and **forbid** {}
   (Lmod 8.7.52+) The *hide* {} function provides a more powerful way to
   hide modules.  The *forbid* {} function provides a way to mark
   modules that exist but cannot be loaded.  See :ref:`modulerc-label`
   for more details.

**Decorations added to --terse output**
  (Lmod 8.7.50+) Lmod now adds decorations to terse output. See
  :ref:`terse_output-label` for more details. 


**MODULES_AUTO_DEFAULT**
   (Lmod 8.7.41+) When this variable is set then Lmod treats *prereq*
   as *depends_on* and *prereq_any* as *depends_on_any*.

**depends_on_any("pkgA*,"pkgB",...)**
   (Lmod 8.7.41+) A new function *depends_on_any()* which works like
   *depends_on()* except that Lmod picks the first available in the
   list. 

**Lmod Warnings**
   (Lmod 8.7.33) Lmod warning nolonger set the error status on exit.

**hook.register(<hook_name>, func, <action>)**
   (Lmod 8.7.25+) The hook.register function now takes a optional third
   argument: action.  The legal actions are the followning strings:
   "replace", "append", "prepend".  See
   :ref:`registering_multiple_hook_functions-label` for more details.


**/etc/lmod/.modulespath**
   (Lmod 8.7.24) Sites can use /etc/lmod/.modulespath or set
   $LMOD_MODULEPATH_INIT during their site's startup scripts to
   control where Lmod finds the .modulespath file.

**check_module_tree_syntax**
   (Lmod 8.4.3+) check_module_tree_syntax is a command to find syntax
   errors in your modulefiles.  It also reports when there are
   modulefile directories that have multiple ways of marking a
   default. See :ref:`checking_syntax-label` for more details.


**module category**
   (Lmod 8.7.14+) Community provided feature from PR #600. This
   command has two levels.  1) "module category" list all the
   categories in the entire module tree; 2) "module category <name1>
   <name2> ..." list the all the modules that have list that
   category.  Note that this listing is case insensitive.  So "Library"
   and "library" will both be printed out when running **module
   category library**

**Collection are written to both ~/.config/lmod and ~/.lmod.d**
   (Lmod 8.7.13+) Lmod is transitioning away from using the ~/.lmod.d
   directory. During transition, collection files are written to both
   directories.  Sites can use the --with-useDotConfigDirOnly=yes or
   set the env. var. **LMOD_USE_DOT_CONFIG_ONLY** to "yes" to complete
   the transition.  Lmod 9+ will force the default to be yes. This
   means that Lmod will only write to ~/.config/lmod but always read
   from both directories.

**User cache files are now written to ~/.cache/lmod**:
   (Lmod 8.7.12+) The old user cache directory was ~/.lmod.d/.cache
   and it has now changed to ~/.cache/lmod/\*.  Lmod is transitioning
   away from using the ~/.lmod.d directory. Also
   the --with-useDotFiles configuration option has been remove as it
   is nolonger needed.

**Controlling installed permission**:
    (Lmod 8.7.11+): Lmod now uses your umask to set permissions unless
    your user id (id -u) is less than UID_MIN (from /etc/login.defs)
    or UID_MIN=500 by default.  In that case, it uses a
    umask of 022.  This translates to 755 for executable files and 644
    for all others.  Sites can override this at configure time with
    **--with-mode=MODE**.

**LMOD_SYSTEM_DEFAULT_MODULES**:
     (Lmod 8.7.7+) If a site has no system default modules they can set this
     variable to **__NO_SYSTEM_DEFAULT_MODULES__**.  This will
     allow **module reset** to purge all modules and reset $MODULEPATH
     to the system default.
     
**Dynamic Spider Cache Support**:
     (Lmod 8.7.4+): If a modulefile changes $MODULEPATH, it is marked
     as dynamic and is re-read when performing a *module spider*.
     This is to allow sites to dynamically add in modulefiles in user
     directories.  This can be turned off at configure time or with by
     setting LMOD_DYNAMIC_SPIDER_CACHE=no.

**Warning when reading too many non-modulefile**:
     Lmod (8.7.4+): To catch directory that are full of
     non-modulefiles, Lmod count the number of regular files that do
     not start with a ".". If there are more than 100, Lmod reports
     a warning.

**Loading a modulefile too many times**:
     (Lmod 8.7.3+): Lmod throws an error if any modulefile is loaded
     500 time or more in a single module command.  This is to prevent
     infinite load loops.

**An unload cannot fail**:
     As of Lmod 8.7+, an error found during unload is treated as a
     warning.

**puts stdout**:
     This TCL modulefile will generate its output at the end of the
     modulefile evaluation and not the beginning. New in Lmod 8.7.
     This matches Tmod 4.1

**puts prestdout**:
     This TCL modulefile will generate its output at the beginning of the
     modulefile evaluation. New in Lmod 8.7. This matches Tmod 5.1.

**LmodBreak**:
     LmodBreak() modulefile function causes the evaluation of the
     current modulefile to stop and all changed in the user's
     environment to be ignored from the current modulefile.  However,
     all other modulefiles are evaluated.  In TCL modulefiles, this
     command is **break**.  Break works normally inside a loop.  If a
     bare break is found outside a loop, it cause the current
     modulefile stop its processing. New in Lmod 8.7+

     **Note** As of Lmod 8.6.16: LmodBreak()/break does nothing when
     unloading. 


**/etc/lmod/lmod_config.lua**:
     Lmod looks for a file named lmod_config.lua in the
     LMOD_CONFIG_DIR which is by default /etc/lmod/lmod_config.lua.
     This file allows sites configure lmod through lua instead
     of setting environment variables by using the cosmit:assigin()
     functions::
         
         cosmit:assign("LMOD_SITE_NAME","XYZZY")

     See :ref:`lmod_config-label` for details.  New in Lmod 8.6+

**LMOD_QUARANTINE_VARS**:

     This is an environment variable containing a list of environment
     variables that Lmod will not change the value of.  Note that this
     only applies to non-path variables.  Variables such as PATH or
     LD_LIBRARY_PATH are ignored in this variable.  In other words,
     Lmod could change any path like variables.  New in Lmod 8.6+

**source_sh** ("shellName","shell_script arg1 ..."):
     source a shell script as part of a module. Supported shellNames
     are *sh*, *dash*, *bash*, *zsh*, *csh*, *tcsh*, *ksh*.  When
     loading, Lmod automatically converts the shell script into module
     commands and saves the module commands in the environment.  It
     does this by sourcing the shell script string in a subshell and
     comparing the environment before and after sourcing the shell
     script string. When unloading, the saved module commands from the
     environment are used.

     See :ref:`sh_to_modulefile-label` for details (New in version 8.6) 
     


**sh_to_modulefile**:
   New in version 8.6, it now track converts alias and shell functions
   as well as environment variables into a modulefile.

**LMOD_SITE_MODULEPATH**:
    An colon separated list of directories to be prepended to
    $MODULEPATH before the first call to the Lmod command.
    See :ref:`lmod_site_modulepath-label` for details
    New in version 8.5.18

**module overview**:
     Similar to **module avail**, this command prints the just
     module name and not the name and the version.  The number of
     versions is printed next to the module name:  For example::

        $ module overview

        ------------ /apps/modulefiles/Core -------------
        StdEnv    (1)   hashrf    (2)   papi        (2)  
        ddt       (1)   intel     (2)   singularity (2)   
        git       (1)   noweb     (1)   valgrind    (1)

    New in version 8.5.10+

**sh_to_modulefile**:
   New in version 8.6, it now track converts alias and shell functions
   as well as environment variables into a modulefile.

**extension()**:
   New in version 8.2.5+, Lmod provides a module function which says
   that these packages available when this module is loaded.  See
   :ref:`extensions-label` for details.
      
**depends_on()**:
  A safe way to have one module load another.  See
  :ref:`dependent_modules-label` for details.  New in version 7.5.12+
