Environment variables in Perl / use Env

If I say use Env;, Perl loads in a module which allows me to access all my environment variables directly within my code, by name. If I add an explicit list of variable names as a list to the module, then only those variables will be imported. So in this example, $PATH prints nothing but $SHELL and $PWD tell you the shell and the present working directory. Extra environment variables can be accessed directly from the %ENV hash (and that can be done whether or not you have called the module in).

# Env brings environment into current namespace

use Env qw(SHELL PWD);

 

print "--- $PATH ---\n";

print "--- $SHELL ---\n";

print "--- $PWD ---\n";

 

print "--- $ENV{PATH} ---\n";

(written 2008-07-11, updated 2008-07-12)

Associated topics are indexed under

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  [386] What is a callback? - (2005-07-22)
  [240] Conventional restraints removed - (2005-03-09)

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There is more that one way - Perl
A Train Service Update for Melksham Party in the Park
Configuring Apache httpd
The Story of Well House Manor
Environment variables in Perl / use Env
Perl ... adding to a list - end, middle, start
Running operating system commands in Perl
Training Course and Business Conference Technology
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