envsubst - substitutes environment variables in shell format strings


   envsubst [OPTION] [SHELL-FORMAT]


   Substitutes the values of environment variables.

   Operation mode:
   -v, --variables
          output the variables occurring in SHELL-FORMAT

   Informative output:
   -h, --help
          display this help and exit

   -V, --version
          output version information and exit

   In  normal operation mode, standard input is copied to standard output,
   with references to environment  variables  of  the  form  $VARIABLE  or
   ${VARIABLE}  being replaced with the corresponding values.  If a SHELL-
   FORMAT is given, only those environment variables that  are  referenced
   in  SHELL-FORMAT  are  substituted; otherwise all environment variables
   references occurring in standard input are substituted.

   When --variables is used, standard input is  ignored,  and  the  output
   consists  of  the  environment  variables that are referenced in SHELL-
   FORMAT, one per line.


   Written by Bruno Haible.


   Report bugs to <bug-gnu-gettext@gnu.org>.


   Copyright  2003-2007 Free Software Foundation, Inc.   License  GPLv3+:
   GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
   This  is  free  software:  you  are free to change and redistribute it.
   There is NO WARRANTY, to the extent permitted by law.


   The full documentation for envsubst is maintained as a Texinfo  manual.
   If  the info and envsubst programs are properly installed at your site,
   the command

          info envsubst

   should give you access to the complete manual.


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