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8.46 Env

Lets your program treat environment variables as simple variables instead of having to access them from the %ENV pseudo-hash where they are kept.

use Env;

use Env qw(
Internally, Env uses an import function that ties suitably named environment variables to global Perl variables with the same names. By default, it ties all variables yielded by keys %ENV . A "suitable" environment has a name that begins with an alphabetic character and contains only alphanumeric characters or underscores.

When use Env is invoked with arguments, the arguments are interpreted as a list of environment variables to tie , but the variables don't have to exist yet. After a variable has been tied, you can use it like a normal variable, accessing or changing its value.

You untie a variable by setting its value to undef .