One potential problem that hasn't been mentioned yet, is that the process may die during the print OUTFILE action, causing some data at the end of the file to be lost. I usually write to a temporary file then rename this temporary file to replace the original file. Renaming is atomic on every system that I'm aware of.

For example: 

# At this point I have created some sort of lock to ensure
# nobody else is going to read or write $infile_name
while (<INFILE>) {    # Using read instead of <INFILE> would be more e
+fficient
    print TEMPFILE;
}
close TEMPFILE
rename $temp_filename, $infile_name or die
# Remove the lock here

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In reply to Re: flock issue by tomhukins
in thread flock issue by airman

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