PERL Logger

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PERL Logger

Mar 1, 2010 12:00 PM, By Chriss Scherer

Tech Tips, March 2010

A Perl of a logger

When it comes to logging a station's stream, there are many products available with a variety of features. But if you're handy with writing scripts, you can create your own. Rob Landry, a contract engineer in Boston, created such a script for one of his clients.

His Perl script records each hour as an MP3 file by capturing the station's Internet stream. Each hour is labeled and placed in a directory for each day (e.g. "wed_dec_16_2009").

#!/usr/bin/perl # ==> AIRCHECK SCRIPT sub log { my $a = shift; my $time = localtime(time); if (open (LOG,">>$LOG")) { print (LOG "$time: $a\n"); close LOG; } } sub purge { my $a = ''; my @stat = (); my $ptime = time - 86400 * $RETAIN; if (opendir (ROOT,$ROOT)) { while ($a = readdir ROOT) { @stat = stat("$ROOT/$a"); if ($stat[9] < $ptime) { if (system("rm -rf $ROOT/$a")) { &log("FAILED: rm -rf $ROOT/$a"); } else { &log("$ROOT/$a purged"); } } } closedir ROOT; } } # ==> MAIN PROGRAM @MON = ('jan','feb','mar','apr','may','jun','jul','aug','sep','oct','nov','dec'); @DAY = ('sun','mon','tue','wed','thu','fri','sat','sun'); @HOUR = ('12mid','1am','2am','3am','4am','5am','6am','7am','8am','9am','10am','11am','12noon','1pm','2pm','3pm','4pm','5pm','6pm','7pm','8pm','9pm','10pm','11pm'); $ROOT = '/var/aircheck'; $RETAIN = 60; $LOG = '/var/aircheck/aircheck.log'; $PERIOD = 3600; # 1 hour $URL = ""; if ($a = fork) { $count = 0; while ($count < $PERIOD) { $count++; sleep 1; } kill 9,$a; wait(); print "exiting\n"; } else { &purge; @time = localtime(time); $wday = $DAY[$time[6; $year = 1900 + $time[5]; $mon = $MON[$time[4; $day = $time[3]; $hour = $HOUR[$time[2; $dir = "$ROOT/$wday\_$mon\_$day\_$year"; if (! (-d $dir)) {system("mkdir $dir")} exec("wget $URL -O $dir/$hour.mp3"); }

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