You give the example of df, and you are right. So avoid calling external programs as far as possible. Try and use internal Perl commands, or use modules that are portable.

$^O ($OSNAME) is a useful variable to test on those occasions when you have to. When you have to use different modules depending on the platform, see the often forgotten pragma if, for example:
use if ($^O eq 'MSWin32'), 'Win32::Process';
use if ($^O ne 'MSWin32'), 'POSIX';

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In reply to Re: Need tips on portable Perl programming by cdarke
in thread Need tips on portable Perl programming by newbie01.perl

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