pam_env -- PAM module to set/unset environment variables

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DESCRIPTION

   The pam_env PAM module allows the (un)setting of environment variables.
   Supported is the use of previously set environment variables as well as
   PAM_ITEMs such as PAM_RHOST.

   By default rules for (un)setting of variables is taken from the config
   file /etc/security/pam_env.conf if no other file is specified.

   This module can also parse a file with simple KEY=VAL pairs on separate
   lines (/etc/environment by default). You can change the default file to
   parse, with the envfile flag and turn it on or off by setting the readenv
   flag to 1 or 0 respectively.

   Since setting of PAM environment variables can have side effects to other
   modules, this module should be the last one on the stack.

OPTIONS

   conffile=/path/to/pam_env.conf

           Indicate an alternative pam_env.conf style configuration file to
           override the default. This can be useful when different services
           need different environments.

   debug

           A lot of debug information is printed with syslog(3).

   envfile=/path/to/environment

           Indicate an alternative environment file to override the default.
           This can be useful when different services need different
           environments.

   readenv=0|1

           Turns on or off the reading of the file specified by envfile (0 is
           off, 1 is on). By default this option is on.

   user_envfile=filename

           Indicate an alternative .pam_environment file to override the
           default. This can be useful when different services need different
           environments. The filename is relative to the user home directory.

   user_readenv=0|1

           Turns on or off the reading of the user specific environment file.
           0 is off, 1 is on. By default this option is off as user supplied
           environment variables in the PAM environment could affect behavior
           of subsequent modules in the stack without the consent of the
           system administrator.

EXAMPLES

   These are some example lines which might be specified in
   /etc/security/pam_env.conf.

   Set the REMOTEHOST variable for any hosts that are remote, default to
   "localhost" rather than not being set at all

       REMOTEHOST     DEFAULT=localhost OVERRIDE=@{PAM_RHOST}


   Set the DISPLAY variable if it seems reasonable

       DISPLAY        DEFAULT=${REMOTEHOST}:0.0 OVERRIDE=${DISPLAY}


   Now some simple variables

       PAGER          DEFAULT=less
       MANPAGER       DEFAULT=less
       LESS           DEFAULT="M q e h15 z23 b80"
       NNTPSERVER     DEFAULT=localhost
       PATH           DEFAULT=${HOME}/bin:/usr/local/bin:/bin\
       :/usr/bin:/usr/local/bin/X11:/usr/bin/X11


   Silly examples of escaped variables, just to show how they work.

       DOLLAR         DEFAULT=\$
       DOLLARDOLLAR   DEFAULT=        OVERRIDE=\$${DOLLAR}
       DOLLARPLUS     DEFAULT=\${REMOTEHOST}${REMOTEHOST}
       ATSIGN         DEFAULT=""      OVERRIDE=\@