++, but if the input doesn't end with a "section" line, the last block will not be printed, so you have to put 
>>>call sort routine<<<
print @unsorted_input;

[download]
after the loop...

In reply to Re^2: Use Perl's Sort to only sort certain lines in a file? by soonix
in thread Use Perl's Sort to only sort certain lines in a file? by grahambuck

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