You could cut out a lot of code by using stat - specifically "mtime", which is the "last modify time in seconds since the epoch". I would suggest putting a small sleep time in the loop as well, just so you're not constantly hitting your machine - unless it's absolutely crucial that you know the second when this file has changed. 

my $file = "somefile.txt";

# Establish a base "last accessed time"
my $lastaccessed = (stat($file))[9]; 

while(1) {
  if ((stat($file))[9] == $lastaccessed) {
    # The file is the same
  } else {
    # File is different
  }
  sleep 5;
}

[download]

Check the docs for stat - it provides a lot of useful info about files.


Rich36
There's more than one way to screw it up...

In reply to Re: Perl process to constantly detect the time change of a file? by Rich36
in thread Perl process to constantly detect the time change of a file? by blackcode6

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