Hi All,
I want to share my recent experience with debugging a code.

Task
I was processing about 500 files through a code that I had refactored extensively.

Problem
I noticed that while most of the files were parsed as expected, about 50 files were much smaller than the expected filesize. I tried rerunning the missing records through the parsing script and it produced the expected result! This was driving me crazy.

Solution
I then used a Perl debugging tool on the original file and ran the script step by step to see why I am getting a smaller file. The culprit was this line in some 500 lines of code: 
if( $variable > $certain_value)
{
    exit;
}

[download]
While this works for most of the files where this condition is not satisfied, certain files do meet this criteria and hence the script exits prematurely!
When I changed this to skip to the next record, it worked like a charm! 
if( $variable > $certain_value)
{
    next RECORD;
}

[download]
Lessons Learned
Even if it takes time to run a script line by line using the debugger, spend this time to save your sanity!

In reply to How a baisc debugging effort restored my sanity! by umasuresh

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