envsubst — substitutes environment variables in shell format strings

Examples (TL;DR)




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.

Reporting Bugs

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

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.

Referenced By


May 2019 GNU gettext-runtime 0.20.7-31105-dirty