Setup Environment variable using perl

Question

I am trying to set environment variable using Perl. It should export this variable outside (in current shell) not just in the script.

I tried:

`setenv X1 /p/fsd`

system("setenv X1 /p/fsd") == 0 or die "failed:$?"

system command "setenv X1 /p/fsd" failed: -1

$ENV{"X1"} = "/p/fsd"; 

Nothing seems to be working.

If it matters i am using TCSH.

Answer 1

$ENV{"X1"} = "/p/fsd"; 

is the right way.

Test in perlconsole :

Perl> $ENV{X1} = "/p/fsd";
/p/fsd

Perl> system('echo $X1');
/p/fsd
0

NOTE

• the single quotes (or backslashing) is required on echo $X1 to prevent perl to interpolate it itself.
• you can't change ENV of parent shell, see http://www.perlmonks.org/?node_id=684685

Answer 2

Equally important to know how to set an env variable is how to delete it:

delete $ENV{"X1"};

This will delete the environment variable for the perl process and any children processes. But the environment variable will still be set for the parent process.