Re: join with header line support

[Assaf Gordon]

Eric,

Thank you for your detailed and quick response.

Eric Blake wrote, On 10/30/2009 07:23 PM:
> The bar is very high for adding new options, especially for burning a
> short option on something that doesn't have much background.  

That's understandable.

A mixture of "head -n 1" to extract the header line, and "tail -n +2" to 
extract the actual data to join, followed by concatenating the files after the join does work with 
the current version of coreutils. It is certainly doable, just a bit cumbersome (especially if one 
needs to extract specific columns).

> You'll need documentation, an addition to the testsuite, mention in the
> NEWS file, and so forth, before this patch could be worthy of inclusion

If you're willing to consider the patch, I will definitely add all required 
files.

> so yes, you would need to
> start the paperwork process of assigning copyright to the FSF; 

Will do (but if I already have the same paper work done for SED and AWK, do I 
need a new one for coreutils?)

> This won't compile.  And even if it did, it doesn't match neighboring
> style.  It's hard to review something that isn't even complete.

The inline patch got messed-up by my email client.
Please, if that's OK, look at the files here:

http://cancan.cshl.edu/labmembers/gordon/coreutils8/join_with_header.patch
http://cancan.cshl.edu/labmembers/gordon/coreutils8/1.txt
http://cancan.cshl.edu/labmembers/gordon/coreutils8/2.txt


Thanks,
  gordon