while Monitoring a folder using File::ChangeNotify module how can i get the file which got modifed

Question

#!/opt/perl_5.18.2/linux50/bin/perl

use strict;
#use warnings;

use File::ChangeNotify;

$| = 1;

my $watcher = File::ChangeNotify->instantiate_watcher(
    directories => [ '/var/icc_shantesh/logs' ],
    filter      => qr/\.log/,
);

while ( my @events = $watcher->wait_for_events ) {
    print "loop got executed\n";
    print "File name: $_\n";
}

I am using File::ChangeNotify in the above code in my R&D environment. The script monitors a folder and informs whenever there is a change. I want to know the name of the file that has changed, and its updated content

Answer 1

The @events array has the information you want:

 while (my @events = $watcher->wait_for_events){
    print "loop got executed\n";
    foreach my $event (@events) {
        print "File name: " . $event->path . "\n";
    }
 }

The array contains File::ChangeNotify::Event objects, and they have a path accessor for filename, and a type for what kind of change has been done.

You could look at the example on the man page and rewrite your code to be like that:

 for my $event ( $watcher->new_events() ) {
     print "File name: ", $event->path(), ' - ', $event->type(), "\n";
 }

$_ is the default variable of perl, but when you explicit set the variable like you do in the loop (my @events = ...) $_ is not being used.