You have to tell perl to actually use the POSIX module. It's not enough to just put it in your @INC path, you have to specifically tell Perl to use it, as follows:

#!/usr/bin/perl

use strict;
use warnings;
use POSIX;    # This line loads the POSIX module and imports pow().

print pow( 2, 3 ); # See? Now it works.
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By the way: my $number = pow( 2, 3 ); could be written like this instead: my $number = 2 ** 3;, and that wouldn't require the use of the POSIX module.

But is there a way by which i can ,sort of autoload all the standard subroutines instead of individually specifying them.

Since there is no agreement on what "all the standard subroutines" should contain, there is no way you can autoload them.

Also it would be quite rare that you need "all the standard subroutines" (whatever they may be) in the same script.

CountZero

"If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law

You need to use use.

use POSIX qw[ pow ];

print pow(2,3);
8

print pow( 1000, 0.33333333333333333 );;
10
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If I understand the docs correctly, POSIX automatically exports pretty much everything except for subroutine names that conflict with Perl built-ins. If you wish to protect your namespace, the easiest way to override this unfortunate behavior is to invoke POSIX like this:

use POSIX (); # Import nothing.

print POSIX::pow( 2, 3 ); # Use the fully-qualified name.
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Dave

Specifying an import list explicitly prevents POSIX from importing anything other than the functions you specify:

c:\test\546536>p1
print scalar keys %main::;; ## Before use POSIX main has how many glob
+als?
67

use POSIX qw[ pow ];;

print scalar keys %main::;; ## and after is has
72
Terminating on signal SIGINT(2)

c:\test\546536>p1
$h{ $_ }++ for keys %main::;; ## Record what we have before

use POSIX qw[ pow ];;

$h{ $_ }++ for keys %main::;; ## Again after

print for grep{ $h{ $_ } == 1 } keys %h;;  ## Display the differences
_<c:/Perl/lib/auto/POSIX/POSIX.dll
XSLoader::
POSIX::
pow
_<POSIX.c
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Two 'private' paths, two new namespaces and one new function (pow) in main.

---

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

This may be a silly question: but why do you want to use the POSIX pow function when Perl has a perfectly good built-in exponentiation operator? Go to perlop and look for "Exponentiation."