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

[download]

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.

In reply to Re^3: standard perl routine by BrowserUk
in thread standard perl routine by rocketboy

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