envsubst - substitutes environment variables in shell format strings

       Written by Bruno Haible.

       Copyright  ©  2003-2024  Free  Software  Foundation,  Inc.   License  GPLv3+:  GNU GPL version 3 or later
       <https://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.

       Substitutes the values of environment variables.

   Operationmode:-v, --variables
              output the variables occurring in SHELL-FORMAT

   Informativeoutput:-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.

       envsubst - substitutes environment variables in shell format strings

       Report  bugs  in  the  bug  tracker  at  <https://savannah.gnu.org/projects/gettext>  or  by   email   to
       <bug-gettext@gnu.org>.

       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

              infoenvsubst

       should give you access to the complete manual.

GNU gettext-runtime 0.23.1                        December 2024                                      ENVSUBST(1)

envsubst [OPTION] [SHELL-FORMAT]