No need to to dupicate all the code (now to make changes it's one place, not two).. 
sub FileMeta {
  my $fh = shift;
  my ($dev, $inode, $size, $mtime) = ($fh ? stat($fh) : stat(_))[0,1,7
+,9];
  return join ":", $size, $dev, $inode, $mtime;
}

[download]
(i also assumed the ';' in the return string was a typo)

Could also do it w/o temp vars: 
sub FileMeta {
  my $fh = shift;
  # glue together the size, dev, inode, and mtime
  return join ":", ($fh ? stat($fh) : stat(_))[7,0,1,9];
}

[download]
Another approach (though you noted avoiding modules) would be to MD5 the string and return that so that .. or to include in the unique string the MD5 of the contents (of course that's more overhead as well).

Also have to toss in the obligatory mention of Tripwire for really robust monitoring/reporting (though of course a little snippet like this is handy for certain cases).

In reply to Re: Did that file change? by davidrw
in thread Did that file change? by ruzam

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