If by alias you mean a second reference to the same variable, you can use standard perl references.

You will probably want to read perlref to get an idea of how that works. There are lots of "special" variables (perlvar), and I cant think of many uses for this, but this certainly works:

#!/usr/bin/perl

use strict;
use warnings;

$_ = "Hello";
print '$_: ' . $_ . "\n";
my $test = \$_;
print '$test: ' . $test . "\n";
print '$$test: ' . $$test . "\n";

print '$|: ' . $| . "\n";
$test = \$|;
print '$test: ' . $test . "\n";
print '$$test: ' . $$test . "\n";

$|++;

print '$|: ' . $| . "\n";
print '$test: ' . $test . "\n";
print '$$test: ' . $$test . "\n";
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This isn't a particularly pretty piece of code, but I've separated it all out so that you can see whats going on.

Could you be more specific with your question? I wonder, why you want an alias to a "perl special variable"?

Why don't you use the special variable itself?

*main::foo = \$/;
print ">$main::foo<";
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Be well,
rir

$ perl -MAlias -E 'alias foo => $!; for (1 .. 10) {$! = $_; say $foo}'
Operation not permitted
No such file or directory
No such process
Interrupted system call
Input/output error
No such device or address
Argument list too long
Exec format error
Bad file descriptor
No child processes
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