env --version (return code: 0)
env (GNU coreutils) 8.25
Copyright (C) 2016 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.
Written by Richard Mlynarik and David MacKenzie.
env --help (return code: 0)
Usage: env [OPTION]... [-] [NAME=VALUE]... [COMMAND [ARG]...]
Set each NAME to VALUE in the environment and run COMMAND.
Mandatory arguments to long options are mandatory for short options too.
-i, --ignore-environment start with an empty environment
-0, --null end each output line with NUL, not newline
-u, --unset=NAME remove variable from the environment
--help display this help and exit
--version output version information and exit
A mere - implies -i. If no COMMAND, print the resulting environment.
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Full documentation at: <http://www.gnu.org/software/coreutils/env>
or available locally via: info '(coreutils) env invocation'