Unix/Linux Shell Grep to cut

Question

I have a file, say 'names' that looks like this

first middle last     userid
Brian Duke Willy      willybd
...

whenever I use the following

line=`grep "willybd" /dir/names`
name=`echo $line | cut -f1-3 -d' '`
echo $name

It prints the following:

Brian Duke Willy      willybd
Brian Duke Willy

My question is, how would I get it to print just "Brian Duke Willy" without first printing the original line that I cut?

What shell are you using that causes the line from the file to be printed? The code you have posted should not give the output you show. — William Pursell, Oct 05 '12 at 00:05
Run `$SHELL -x yourscript` and look at the value assigned to `line`; is one or two lines? — Jonathan Leffler, Oct 05 '12 at 00:18

William Pursell · Answer 1 · 2012-10-05T00:13:29.353

3

The usual way to do this sort of thing is:

awk '/willybd/{ print $1, $2, $3 }' /dir/names

or, to be more specific

awk '$4 ~ /willybd/ { print $1, $2, $3 }' /dir/names

or

awk '$4 == "willybd" { print $1, $2, $3 }' /dir/names

edited Oct 05 '12 at 00:13

answered Oct 05 '12 at 00:02

William Pursell

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score 1 · Answer 2 · edited Oct 05 '12 at 00:19

1

grep "willybd" /dir/names | cut "-d " -f1-3

The default delimiter for cut is tab, not space.

edited Oct 05 '12 at 00:19

Jonathan Leffler

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answered Oct 04 '12 at 23:20

DrC

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score 0 · Answer 3 · answered Oct 04 '12 at 23:19

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Unless you need the intermediate variables, you can use

grep "willybd" /dir/names | cut -f1-3 -d' '

One of the beautiful features of linux is that most commands can be used as filters: they read from stdin and write to stdout, which means you can "pipe" the output of one command into the next command. That's what the | character does. It's pronounced pipe.

answered Oct 04 '12 at 23:19

Adam Liss

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Funny, I ran the commands you listed, and as I expected, it didn't print the original line. Are you sure you didn't `$echo $line`? Otherwise, I'm not sure why my one-line version would behave differently from yours. – Adam Liss Oct 04 '12 at 23:29

Unix/Linux Shell Grep to cut

3 Answers3