Very Computer

Quote:

>Hello.

>Could someone please tell me
>how I could use sed or awk
>to strip a file of all but
>it's first column?

>e.g.
>           i want a dog                  i
>           don't want a cat        ===>  don't
>           scratching it's claws         scratching
>           all over my back              all

AWK script would be ...
{ print $1 }

and then you would execute this on the command-line ...

AWK -f [script file] [data file] > output.file (if you want to save the
output)

note:  there are other elegent ways of doing the above, but this
        example is probably the easiest way to think about it.

-Bob-

Bob Angell                               | Data Integration (multi-platform)
Principal, Management Systems Engineer   | Health Systems Engineering
Applied Information & Management Systems | Database design/development
1238 Fenway Avenue - SLC, UT 84102-3212  | Simulation/Modeling/Neural Nets

     [Standard Disclaimer: Speaking for the University of Utah, NOT!]

Quote:>Could someone please tell me
>how I could use sed or awk
>to strip a file of all but
>it's first column?

or

sed 's/\([^     ][^     ]*\)\(.*\)/\1/' file

(where [^     ] contains three characters inside the brackets:  
^, blank, and tab).

Both will preserve empty lines; you can delete empty lines as well with

awk 'NF > 0 {print $1}' file

and

sed '/^$/d
     s/\([^     ][^     ]*\)\(.*\)/\1/' file

respectively.
--
Jim Davis             | "Put the underwears in the bag and nobody gets hurt!"