Given a job specification in crontab, is there any way to get the list of dates and times the job in cron will run in the next week?For example, given a string 10 13 * * *, is there any way to get from cron or a similar builtin or utility the (ideally sorted) list of times when the job will run in the next week?
Get chronological list of dates & times for scheduled tasks in cron
shell;cron
You can use this perl script :#!/usr/bin/perl# Base on http://search.cpan.org/~pkent/Schedule-Cron-Events-1.8/cron_event_predict.plx# initial release 20091001use warnings;use strict;use Schedule::Cron::Events;use Getopt::Std;use Time::Local;use vars qw($opt_f $opt_h $opt_p);getopts('p:f:h');if ($opt_h) { usage(); }my $filename = shift || usage();my $future = 2;if (defined $opt_f) { $future = $opt_f; }my $past = 0;if (defined $opt_p) { $past = $opt_p; }open (IN, <$filename) || die Unable to open '$filename' for read: $!;while(<IN>) {    my $obj = new Schedule::Cron::Events($_) || next;    chomp;    print # Original line: $_\n;    if ($future) {        for (1..$future) {                my $date = localtime( timelocal($obj->nextEvent) );                print $date - predicted future event\n;        }    }    $obj->resetCounter;    if ($past) {        for (1..$past) {                my $date = localtime( timelocal($obj->previousEvent) );                print $date - predicted past event\n;        }    }    print \n;}close IN;sub usage {    print qq{SYNOPSIS$0 [ -h ] [ -f number ] [ -p number ] <crontab-filename>Reads the crontab specified and iterates over every line in it, predicting when each cron event in the crontab will run. Defaults to predicting the next 2 events.    -h - show this help    -f - how many events predited in the future. Default is 2    -p - how many events predicted for the past. Default is 0.EXAMPLE$0 -f 2 -p 2 ~/my.crontab\$Revision\$};    exit;}=pod=head1 NAMEcron_event_predict - Reads a crontab file and predicts when event will/would have run=head1 SYNOPSIScron_event_predict.plx [ -h ] [ -f number ] [ -p number ] <crontab-filename>=head1 DESCRIPTIONA simple utility program mainly written to provide a worked example of how to use the module,but also of some use in understanding complex or unfamiliar crontab files.Reads the crontab specified and iterates over every line in it, predicting when each cron event in the crontab will run. Defaults to predicting the next 2 events.These are the command line arguments:    -h - show this help    -f - how many events predited in the future. Default is 2    -p - how many events predicted for the past. Default is 0.Here's an example, showing the default of the next 2 predicted occurences of the each cron job:    dev~/src/cronevent > ./cron_event_predict.plx ~/bin/crontab    # Original line: 1-56/5 * * * * /usr/local/mrtg-2/bin/mrtg /home/admin/mrtg/mrtg.cfg    Thu Sep 26 00:41:00 2002 - predicted future event    Thu Sep 26 00:46:00 2002 - predicted future event    # Original line: 34 */2 * * * /home/analog/analogwrap.bash > /dev/null    Thu Sep 26 02:34:00 2002 - predicted future event    Thu Sep 26 04:34:00 2002 - predicted future event    # Original line: 38 18 * * * /home/admin/bin/allpodscript.bash > /dev/null    Thu Sep 26 18:38:00 2002 - predicted future event    Fri Sep 27 18:38:00 2002 - predicted future eventAnd here's an example showing past events too:    dev~/src/cronevent > ./cron_event_predict.plx -f 1 -p 3 ~/bin/crontab    # Original line: 1-56/5 * * * * /usr/local/mrtg-2/bin/mrtg /home/admin/mrtg/mrtg.cfg    Thu Sep 26 00:41:00 2002 - predicted future event    Thu Sep 26 00:36:00 2002 - predicted past event    Thu Sep 26 00:31:00 2002 - predicted past event    Thu Sep 26 00:26:00 2002 - predicted past event    # Original line: 34 */2 * * * /home/analog/analogwrap.bash > /dev/null    Thu Sep 26 02:34:00 2002 - predicted future event    Thu Sep 26 00:34:00 2002 - predicted past event    Wed Sep 25 22:34:00 2002 - predicted past event    Wed Sep 25 20:34:00 2002 - predicted past event    # Original line: 38 18 * * * /home/admin/bin/allpodscript.bash > /dev/null    Thu Sep 26 18:38:00 2002 - predicted future event    Wed Sep 25 18:38:00 2002 - predicted past event    Tue Sep 24 18:38:00 2002 - predicted past event    Mon Sep 23 18:38:00 2002 - predicted past event=cutSAMPLE OUTPUT:# Original line: 03 05 * * *    /bin/bash command1Thu Dec 25 05:03:00 2014 - predicted future eventFri Dec 26 05:03:00 2014 - predicted future event# Original line: 10 06 * * * size=$(du -h ~/.xsession-errors); [[ $size =~ ^[O-9]+G ]] && :> ~/.xsession-errors Thu Dec 25 06:10:00 2014 - predicted future eventFri Dec 26 06:10:00 2014 - predicted future event# Original line: 21 06 * * 1 perl WWW::Monitor.plMon Dec 29 06:21:00 2014 - predicted future eventMon Jan  5 06:21:00 2015 - predicted future event