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(var1 var2 ...);
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
.
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