According to Benchmark, POSIX::mktime is about 700% faster. 

Benchmark: timing 20000 iterations of POSIX, timelocal...
     POSIX:  1 wallclock secs ( 0.57 usr +  0.03 sys =  0.60 CPU) @ 33
+333.33/s (n=20000)
 timelocal:  6 wallclock secs ( 4.95 usr +  0.00 sys =  4.95 CPU) @ 40
+40.40/s (n=20000)
             Rate timelocal     POSIX
timelocal  4040/s        --      -88%
POSIX     33333/s      725%        --

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Being written in Perl, and not C, Time::Local should work everywhere Perl does. And looking at the source, I don't see anything that may fail as long as Perl is working properly.

According to the docs of Time::Local

Please note, however, that the range of dates that can be actually be handled depends on the size of an integer (time_t) on a given platform. Currently, this is 32 bits for most systems, yielding an approximate range from Dec 1901 to Jan 2038.
And as POSIX::mktime() returns undef when I try to give it a date past 2038, I assume it fails for the same reason.

In reply to Re: POSIX::mktime vs. Time::Local - Revisited. by Paladin
in thread POSIX::mktime vs. Time::Local - Revisited. by BigLug

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