The $^O special variable will tell you the OS you're running on, so you could do something like:
if ($^O eq 'MSWin32') {
    # do something Win32ish
}
else {
    # do something Unixy
}

[download]
See also perlfaq8.

In reply to Re: Porting code between NT/Unix by myocom
in thread Porting code between NT/Unix by Anonymous Monk

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