The load time of Perl is small enough that you can use the esoteric $^T here and not lose any accuracy (at least, not enough to matter; if you were using Time::HiRes it would :)

#!/usr/bin/perl
#Usage: "script.pl INT" [INT = any # (5000+ to see anything)]
print++$_,"\r"while$_<$ARGV[0];print$/,abs($^T-time),"s$/"
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jynx