O wise ones - I'm having a brain freeze.

I have 6 text files of the format SHA-1<tab>7_hex_chars<newline> and each file has 9,000,000 lines. The 6 files are in the same order, with the SHA-1 being the key column of all the files. I can't slurp it all in, and I'm not wild about 6 open files at once, but that may be unavoidable.

I need to munge these together with the result of having six 7-hex-char strings on each line, the 6 values corresponding to the key SHA-1. I don't care if there is a separator, or what it is. Here's a very simple example: 

file_1
123412341234etc   1000001
567856785678etc   5000001
...

file_2
123412341234etc   1000002
567856785678etc   5000002
...

file_3
123412341234etc   1000003
567856785678etc   5000003
...

munged output
1000001 1000002 1000003 ...
5000001 5000002 5000003 ...

[download]

I'm brain dead at the moment, if anyone can suggest a solution in perl (5.8 preferred) or a linux/BSD system tool, I'd appreciate it.

In reply to join on 6 huge files by dwhite20899

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