NAME
envsubst - substitutes environment variables in shell format strings
SYNOPSIS
envsubst [OPTION] [SHELL-FORMAT]
DESCRIPTION
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.
AUTHOR
Written by Bruno Haible.
REPORTING BUGS
Report bugs to <bug-gnu-gettext@gnu.org>.
COPYRIGHT
Copyright (C) 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.
SEE ALSO
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.