zcat two files


 
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# 8  
Old 10-04-2012
Quote:
Originally Posted by drl
My experience is that unzipping the combined file results in the constituent files being effectively catted together.
Well, yes; that's kind of the point. Smilie

I hadn't believed gzip would be capable of this -- gz file essentially has to catch the file starting over -- but it certainly appears to work.

This trick also works with bzip2, xz, and lzop ( though the latter warns about a multipart file ) -- but not with p7zip, lzma, or old-fashioned compress.
# 9  
Old 10-04-2012
Hi, Corona688.

I'm not sure that we're talking about the same thing.

One rarely cats files together -- we keep files separate to distinguish something that characterizes the content. If we unzip a file that was created from a number of gz files, then the result is one huge file, with no way to distinguish among the data in the original files. If we want that, then it seems slightly easier to cat the raw files together, then gzip that file.

I suppose there might situations where we don't care about the separation -- where the content might effectively allow the data to be separated if necessary, date/time data for example, one data file after another, eliminating the need to gzip the entire file time after time. I haven't seen the need for that in my work, but I can easily imagine that there are such situations.

Best wishes ... cheers, drl
# 10  
Old 10-04-2012
Quote:
Originally Posted by drl
Hi, Corona688.

I'm not sure that we're talking about the same thing.

One rarely cats files together
...except this OP. Taking it at face value, that's really, genuinely, and unambiguously what they want.
# 11  
Old 10-04-2012
cat dogging you?
# 12  
Old 10-04-2012
Hi.
Quote:
Originally Posted by jacobs.smith
I have more than 10 files each of 20GB.
OK, apparently only ambiguous to me Smilie -- no more quibbles on this thread from me ... cheers, drl
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