I prefer to use regexps instead of your example due to brevity of handling the failure cases. Even so, you can tweak yours to be a bit more resilant.

This bit doesn't take into account not having 30 characters before the search string: 

  $idx = index( $line, "Search String", 16 );

[download]
Since we know there must be 30 bytes of data before the Search String, do this: 
  $idx = index($line, "Search String", 16+30);

[download]
The same idea is true for the "third_part" bit in your code and isn't hard to handle.

In reply to Re^2: regex man they are tough by cazz
in thread regex man they are tough by tgolf4fun

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