I had to sort out which cron jobs were running during a defined period (04:00 - 06:00 on Monday morning) which should be easy but it wasn't. A co-worker gave me a bit of code which I messed around with and this is the result.
It should work on any system where 'crontab -l [<user>]' is valid and which has perl installed.
It does very little data vetting and is a little short on comments but, as it merely reads from crontab -l and writes to stdout it should be harmless.
The print_usage subroutine says it all.
Ceci n'est pas une signature
Columb Healy
It should work on any system where 'crontab -l [<user>]' is valid and which has perl installed.
It does very little data vetting and is a little short on comments but, as it merely reads from crontab -l and writes to stdout it should be harmless.
The print_usage subroutine says it all.
Code:
#!/usr/bin/perl -w
use strict;
use Getopt::Std;
sub print_usage
{
print @_;
print "Usage $0 [-m minute] [-h hour] [-d day] [-u user]
hour minute and day can be either numeric or nn-nn
example
$0 -d2 -m30-59 -h16
will show all root cron jobs timed between 16:30 and 16:59 inc
on Wednesday\n";
exit 1;
}
my %opts;
getopts ( 'h:d:m:u:', \%opts );
my ( @min_vals, @max_vals );
my @long_days = qw ( Mon Tue Wed Thu Fri Sat Sun );
sub parse_entry
{
my ( $arref, $data, $type ) = @_;
my ($min, $max);
$min = $min_vals[$type]; $max = $max_vals[$type];
$data =~ /^\d+$/ and do
{
( $data >= $min ) && ( $data <= $max ) and (push @$arref, $data);
return;
};
$data =~ /^(\d+)-(\d+)$/ and do
{
$min = ( $1 > $min ) ? $1 : $min;
$max = ( $1 < $max ) ? $1 : $max;
};
$max or return;
while ( $min <= $max )
{ push @$arref, $min; $min++; }
}
$opts{'d'} and do
{{
$opts{'d'} =~ /^\d+$/ and
$min_vals[0] = $opts{'d'}, $max_vals[0] = $opts{'d'}, last;
$opts{'d'} =~/^(\d+)-(\d+)$/ and
$min_vals[0] = $1, $max_vals[0] = $2, last;
print_usage "Invalid day format";
}}
or $min_vals[0] = 0, $max_vals[0] = 6;
$opts{'h'} and do
{{
$opts{'h'} =~ /^\d+$/ and
$min_vals[1] = $opts{'h'}, $max_vals[1] = $opts{'h'}, last;
$opts{'h'} =~/^(\d+)-(\d+)$/ and
$min_vals[1] = $1, $max_vals[1] = $2, last;
print_usage "Invalid hour format";
}}
or $min_vals[1] = 0, $max_vals[1] = 23;
$opts{'m'} and do
{{
$opts{'m'} =~ /^\d+$/ and
$min_vals[2] = $opts{'m'}, $max_vals[2] = $opts{'m'}, last;
$opts{'m'} =~/^(\d+)-(\d+)$/
and $min_vals[2] = $1, $max_vals[2] = $2, last;
print_usage "Invalid min format";
}}
or $min_vals[2] = 0, $max_vals[2] = 59;
my $user = $opts{'u'} ? $opts{'u'} : "";
my %commands;
foreach ( `crontab -l $user` )
{
/^\s*#/ and next;
my ( @mins, @hours, @days );
my ( $minute, $hour, undef, undef, $day, @cmd ) = split / +/;
parse_entry ( \@mins, $minute, 2 );
parse_entry ( \@hours, $hour, 1 );
parse_entry ( \@days, $day, 0 );
foreach my $d ( @days )
{
exists $commands{$d} or $commands{$d} = {};
foreach my $h ( @hours )
{
exists $commands{$d}{$h} or $commands{$d}{$h} = {};
foreach my $m ( @mins )
{
exists $commands{$d}{$h}{$m} or $commands{$d}{$h}{$m} = [];
push @{$commands{$d}{$h}{$m}}, join ' ', @cmd;
}
}
}
}
foreach my $d ( sort { $a <=> $b }keys %commands )
{
foreach my $h ( sort { $a <=> $b } keys %{$commands{$d}} )
{
foreach my $m ( sort { $a <=> $b } keys %{$commands{$d}{$h}} )
{
foreach ( @{$commands{$d}{$h}{$m}} )
{ printf "%s %2.2d:%2.2d %s", $long_days[$d], $h, $m, $_; }
}
}
}Ceci n'est pas une signature
Columb Healy