Name

unsetenv — unset an environment variable mask then chain

Synopsis

unsetenv {var} {next-prog}

NOTE

C-shells have a built-in unsetenv command that does not chain. See the manual for each individual shell for its built-in command.

Description

unsetenv is a chain-loading utility that unsets the environment variable var and then chain loads to next-prog with the execvp(3) function.

next-prog may contain its own command line options, which unsetenv will ignore.

Unsetting a variable is not the same as setting it to an empty value. For that, see setenv(1).

If var contains an equals character, counter-intuitive things will happen to the environment.

BUGS

As of version 1.34 this program no longer employs the GNU C library nor the BSD C library for environment variable handling. The previously documented workaround for those libraries' have memory leaks in their setenv(3) and clearenv(3) functions, is therefore no longer necessary.

See also

  • clearenv(1)

Author

Jonathan de Boyne Pollard