Be warned. In Linux you generally should set the environment variable LC_ALL to C before using sort. Otherwise its idea of sorted order does potentially inconvenient things like: 
1,10
11,1
1,123

[download]
(What? You were expecting all of the things with ID 1 to be grouped together? Silly programmer, read the documentation!)

In reply to Re^3: Compare large files by tilly
in thread Compare large files by boardryder

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