Y'know, Sort::External is designed for exactly what the original poster wants to do... but few people seem to find it on CPAN.

Sort::External was my first CPAN distro, and the people on the modules mailing list prevailed upon me to release it it under the academically correct name. I occasionally regret having taken that advice.

FWIW, here's the definition of "external sort" from nist.gov:

Any sort algorithm that uses external memory, such as tape or disk, during the sort. Since most common sort algorithms assume high-speed random access to all intermediate memory, they are unsuitable if the values to be sorted don't fit in main memory.
--
Marvin Humphrey
Rectangular Research ― http://www.rectangular.com

In reply to Re^3: Sorting a (very) large file by creamygoodness
in thread Sorting a (very) large file by condar

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