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use the -s operator to determine the file's size, and set the $/ special variable to equal 1/4th of the size returned by -s. Then read in a while() loop, just like you always would.

See perlvar for an explanation of how to set $/, and perlfunc -X to learn about -s

...or, again use -s, and then seek to specific locations and use sysread with a length of 1/4th of the total. But then beware of off-by-one errors.

Of course with any of these methods, you're going to run into some memory constraints; reading 25% of a 10GB file will consume 2.5GB. Might be better to set $/ to 1/16th of the file size, and then read/write four times for each output file.


Dave


In reply to Re: Split file into 4 smaller ones by davido
in thread Split file into 4 smaller ones by Anonymous Monk

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