Update: A somewhat more robust version. It correctly handles all but a dozen or so of the 6000+ exes and dlls on my system, though a couple of dozen more have timestamps well in the future (which is noted).

#! perl -slw
use strict;

open EXE, '<:raw', $ARGV[0] or die "$ARGV[0] : $!";
my $dos = do{ local $/ = \65536; <EXE> };
die "$ARGV[0] is not a .exe or .dll (sig='${ \substr $dos, 0, 2 }')"
    unless substr( $dos, 0, 2 ) eq 'MZ';

my $coffoff = 8+ unpack 'x60 V', $dos;
read( EXE, $dos, $coffoff - 65536 + 4, 65536 ) 
    or die $! if $coffoff > 65536;
    
my $ts = unpack "x$coffoff V", $dos;

print "$ARGV[0] : ", scalar( localtime $ts) || "has unfathomable times
+tamp value $ts" );
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Try this

#! perl -slw
use strict;

open EXE, '<:raw', $ARGV[0] or die "$ARGV[0] : $!";
my $dos = do{ local $/ = \1024; <EXE> };
die "$ARGV[0] is not a .exe or .dll" unless substr( $dos, 0, 2 ) eq 'M
+Z';

my $coffoff = 8+ unpack 'x60 V', $dos;
my $ts = unpack "x$coffoff V", $dos;

print scalar localtime $ts;
__END__
C:\cl>p:exetime.pl atlprov.dll
Sat Jan  5 11:46:16 2002

C:\cl>p:exetime.pl cl.exe
Sat Jan  5 10:48:19 2002
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