Diff'ing dates (solved)

LighthouseJ has asked for the wisdom of the Perl Monks concerning the following question:

I'm trying to find the difference in seconds between two dates. The two (and only two) dates come as standard out like:

Sun 09 30 06 42 36 2007
Tue 10 02 06 01 55 2007
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(Note: the months correspond to September and October respectively.)

I tried to do this with awk because I use awk in plenty of other places but awk's mktime() is a GNU-only addition it seems and I only have access to barebones Solaris installs. The only alternative remaining I think is Perl's timelocal function in Time::Local which I believe is a part of the standard install, right? My goal is to put a Perl one-liner in a sh script and this is the last piece in the pipe. I've already written a Perl script which works but purely as an exercise for the monkish community, where are the improvements I'm missing?

Here's what I have currently but I am actively working on it though:

my @array;
while (<>) {
    chomp;
    my @fields = split;
    shift @fields;
    unshift(@fields, pop(@fields));
    $fields[1]--; # decrement the month, timelocal is zero-based
    push (@array, timelocal (reverse @fields));
}

print $array[1] - $array[0];
[download]

"The three principal virtues of a programmer are Laziness, Impatience, and Hubris. See the Camel Book for why." -- `man perl`

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Re: Diff'ing dates by ikegami (Patriarch) on Oct 02, 2007 at 13:33 UTC
`perl -MTime::Local -lane"END{print$t[1]-$t[0]}$F[1]--;push@t,timelocal +@F[5,4,3,2,1,6]"` [download] Update: `perl -MTime::Local -lane"END{print$t}$F[1]--;$t+=($.2-3)timelocal@F[ +5,4,3,2,1,6]"` [download]	[reply] [d/l] [select]
Re^2: Diff'ing dates by LighthouseJ (Sexton) on Oct 02, 2007 at 14:33 UTC
Using your inspiring one-liner, I morphed my script with yours and came up with this: `/bin/perl -MTime::Local -ne '{$t[1]-- && push(@epochs,timelocal(@t[5,4,3,2,1,6])) if (@t=split)} END { print $epochs[1] - $epochs[0]; }'` The END block is most likely what will change because the value of the diff will be used to determine exit status. Thanks a lot for the fresh perspective, it was very helpful. "The three principal virtues of a programmer are Laziness, Impatience, and Hubris. See the Camel Book for why." -- `man perl`	[reply] [d/l]
Re^3: Diff'ing dates by ikegami (Patriarch) on Oct 02, 2007 at 14:50 UTC
The exit code can be controled as follows: `END { exit 1+($epochs[0] <=> $epochs[1]) }` [download] `0: first time is earlier 1: both times are the same 2: second time is earlier` [download] `perl -MTime::Local -lane'END{exit 1+($d<=>0)}$F[1]--;$d+=($.2-3)time +local@F[5,4,3,2,1,6]'` [download]	[reply] [d/l] [select]
Re^4: Diff'ing dates by LighthouseJ (Sexton) on Oct 02, 2007 at 15:30 UTC
Re^2: Diff'ing dates by LighthouseJ (Sexton) on Oct 02, 2007 at 14:19 UTC
I tried the command and this is what I got: `$ echo -e "Sun 09 30 06 42 36 2007\nTue 10 02 06 01 55 2007\n" \| perl +-MTime::Local -lane"END{print$t}$F[1]--;$t+=($.2-3)timelocal@F[5,4, +3,2,1,6]" Can't modify single ref constructor in postdecrement (--) at -e line 1 +, near "]--" syntax error at -e line 1, near "+=" Execution of -e aborted due to compilation errors.` [download] "The three principal virtues of a programmer are Laziness, Impatience, and Hubris. See the Camel Book for why." -- `man perl`	[reply] [d/l]
Re^3: Diff'ing dates by shmem (Chancellor) on Oct 02, 2007 at 14:47 UTC
Use single quotes on UNIX-like operating systems: `echo -e "Sun 09 30 06 42 36 2007\nTue 10 02 06 01 55 2007\n" \| \ perl -MTime::Local -lane 'END{print$t}$F[1]--;$t+=($.2-3)timelocal@F +[5,4,3,2,1,6]'` [download] Double quotes cause your shell to interpret e.g. `$t` as a shell variable. --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---------------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply] [d/l] [select]
Re^3: Diff'ing dates by ikegami (Patriarch) on Oct 02, 2007 at 14:43 UTC
Use the appropriate quotes for your shell. Switch double quotes for single quotes.	[reply]
Re^4: Diff'ing dates by LighthouseJ (Sexton) on Oct 02, 2007 at 15:23 UTC
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