How about Tie::File? From what I understand, it does not store the file in memory, could be suitable?

We have a list of all possible regular expression matching a sequence header for the fastqs that we are working with. Say for a set of 4 lines, you would have:

@BLABLA:1:2:3:2
ACGTACGT...
+
DDDEEHFG...

[download]

So all headers are:

 ^@\S+:\d+:\d+:\d+:\d+\n

But headers are not of a fixed length, so how would you seek into a file if you need the byte start and end position?

In reply to Re^4: multiple processes to access one file by Anonymous Monk
in thread multiple processes to access one file by julio_514

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