Perl date conversion

gio001 has asked for the wisdom of the Perl Monks concerning the following question:

Hello everyone, I am using the following Perl one liner in a ksh script to process a file of dates and change them to a different format and attach a counter of 1 to each date processed. I must have something wrong, when I have entries like:

 
1300483666
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which is Fri Mar 18 17:27:46 2011 for which I would expect an output of the form:

2011 03 18 05 21      1
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this code returns:

2011 03 18 05 17      1
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This is the code I use :

perl -lne '($j1,$j2,$hour,$mday,$mon,$year,$wday) = gmtime($_);$year =
+ $year + 1900;$mon++;printf("%4s %.2d %.2d %.2d %.2d %6s\n",$year,$mo
+n,$mday,$wday,$hour,1);' < inputFile >outputFile
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I really hope someone can help and explain my error. Thanks!

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Re: Perl date conversion by Fletch (Bishop) on Mar 23, 2011 at 18:22 UTC
Use `strftime` from POSIX (granted it only prints the day-of-week as only a single digit so it's not 100% equivalent if (e.g.) you need fixed columns) `perl -MPOSIX=strftime -lne 'print strftime("%Y %m %d %w %H\t1",localti +me($_))'` [download] The cake is a lie. The cake is a lie. The cake is a lie.	[reply] [d/l] [select]
Re: Perl date conversion by toolic (Bishop) on Mar 23, 2011 at 17:24 UTC
I can not reproduce your results. Are you sure your input file is what you think it is? `echo 1300483666 \| perl -lne '($j1,$j2,$hour,$mday,$mon,$year,$wday) = +gmtime($_);$year = $year + 1900;$mon++;printf("%4s %.2d %.2d %.2d %.2 +d %6s\n",$year,$mon,$mday,$wday,$hour,1);' 2011 03 18 05 21 1` [download]	[reply] [d/l]
Re^2: Perl date conversion by gio001 (Acolyte) on Mar 23, 2011 at 17:45 UTC
My message is incorrect, I want to have this output from an input of `1300483666`: `2011 03 18 05 17 1` and instead the code returns: `2011 03 18 05 21 1` Sorry for the mistake. Can you help? I suppose I can make the `gmtime($_)`be like `gmtime($_-14400)` but I thought there might be a cleaner way to resolve the date in input to my local time (EST or EDT whatever it happens to be). Can I do without the gmtime all together? Hope you can help. Thanks	[reply] [d/l] [select]
Re^3: Perl date conversion by gio001 (Acolyte) on Mar 23, 2011 at 17:58 UTC
I replaced gmtime with localtime and it seems to work properly. Thanks Any advice anyway?	[reply]
Re^4: Perl date conversion by ikegami (Patriarch) on Mar 23, 2011 at 18:34 UTC