man envsubst (Commandes) - substitutes environment variables in shell format strings
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 © 2003-2005 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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.