Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!thunder.mcrcim.mcgill.edu!mouse
From: mouse@thunder.mcrcim.mcgill.edu (der Mouse)
Newsgroups: comp.unix.questions
Subject: Re: file manipulation (easy question I think - REWORDED)
Keywords: awk sed
Message-ID: <1991Jun20.092927.160@thunder.mcrcim.mcgill.edu>
Date: 20 Jun 91 09:29:27 GMT
References: <1991Jun18.014539.22085@msuinfo.cl.msu.edu> <1991Jun18.195126.9916@gorm.ruc.dk>
Organization: McGill Research Centre for Intelligent Machines
Lines: 23

In article <1991Jun18.195126.9916@gorm.ruc.dk>, jba@gorm.ruc.dk (Jan B. Andersen) writes:
> jpd@tardis.cl.msu.edu (Joe P. DeCello) writes:
>> I would like to be able to output the first field of each line into
>> a new file.  I would like these fields to be on one line in the new
>> file and separated by commas.

> Easy. We'll use cut(1) to select field no. 1 using ':' as the
> delimiter, and will then use tr(1) to translate the newlines into
> commas:

>   $ cat OLDFILE | cut -d: -f1 | tr "\012" "," > NEWFILE

> The only problem is what to do with the last comma?

Not the only problem; you're also missing the trailing newline.

< OLDFILE awk -F: 'BEGIN { pref = ""; } { printf("%s%s",pref,$1); pref = ","; } END { printf("\n"); }' > NEWFILE

					der Mouse

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