A more Unix-y way to do this would be to use the alarm function. See 'perldoc -f alarm' for details.

#!/usr/bin/perl
use strict;
my $interval = 60; # seconds between calls
                                                                      
+          
# sub will be called every $interval seconds
my $process = sub {
   print "processing!\n"
};
                                                                      
+          
# engage the alarm system
$SIG{ALRM} = sub { 
   &$process; 
   alarm $interval; 
};                                                                    
+            
alarm $interval;
                                                                      
+          
# function will be called every 60 seconds for rest of program...
[download]

Another alternative would be to upgrade the program to use POE events. This would be the route I would take. The alarm demo is more for historical interest and fiddling than for anything else.