topic Re: Field seperator help in Operating System - Linux

Field seperator help

Gordon_3 — Fri, 21 Apr 2006 04:42:47 GMT

Hi all,

Suppose get below output:

0% ( 0%) 0% ( 0%) Apr 20 19:04 backup
1% ( 0%) 0% ( 0%) Apr 20 19:04 backup

How can I get the field of "Apr" in the script? I try awk , but seems not a good solution as it may go to "20" in some case..Thx.

Bgds,
Gordon

Re: Field seperator help

Chan 007 — Fri, 21 Apr 2006 04:47:59 GMT

Hi Gordon,

Have you tried,

if the name of the file is test

cat test|awk '{print $5}'

I assume you have only 4 spaces

Chan

Re: Field seperator help

Gordon_3 — Fri, 21 Apr 2006 04:51:05 GMT

HI Chan,

I suppose u mean $7 :)

OK the thing is, somehow for below output

51% (13%) 0% ( 0%) Apr 20 19:03 backup

$7 will be "20" instead of "Apr", I think the '51' field has some tricky stuff there making it NOT generic to use awk...

Bgds,
Gordon

Re: Field seperator help

Peter Godron — Fri, 21 Apr 2006 04:54:14 GMT

Gordon,
the problem is the number of spaces.
If you have a fixed number of spaces
echo "0% ( 0%) 0% ( 0%) Apr 20 19:04 backup" | cut -d' ' -f7
or
If you have a fixed length for each field
echo "0% ( 0%) 0% ( 0%) Apr 20 19:04 backup" | cut -c19-22

Re: Field seperator help

Gordon_3 — Fri, 21 Apr 2006 04:54:16 GMT

Ok some correction, it's due to 13%, coz it fill up all space there and so awk treat that 1 field instead of 2 field... so that's why awk 'not' generic here

Re: Field seperator help

Gordon_3 — Fri, 21 Apr 2006 04:57:10 GMT

Thx peter, seems using character count can deal with this problem effectively !

Re: Field seperator help

James R. Ferguson — Fri, 21 Apr 2006 05:15:43 GMT

Hi Gordon:

This will extract the field "Apr" (or any three character month) from the format you show:

# perl -nle 'print $1 if /^\d+%.+\)\s+(...)/' file

Regards!

...JRF...

Re: Field seperator help

Philippe Vervoort — Mon, 24 Apr 2006 04:53:15 GMT

Hello,

Another way to use awk is to 'count backward', as it seems the first fields are not always equal in length.

awk '{print $(NF-3)}' test

if your file is called 'test'

Greetings,
Philippe