Command to separate 2nd line's 3rd word from a text file

senthilvael · 11-29-2007, 11:02 AM

HI,
Please suggest me the command in linux to separate second line's 3rd word from a text file.

matthewg42 · 11-29-2007, 11:09 AM

awk would be ideal.

pixellany · 11-29-2007, 02:33 PM

Code:

cat filename |sed -n '2p'|cut -d " " -nf 3

Assumes that words are delimited by exactly one space. If more than one space, add another sed to replace N spaces with one.

Not tested:

Code:

sed '/ */ /g'

matthewg42 · 11-29-2007, 02:45 PM

Code:

awk 'NR==2 { print $3 ; exit }'

pixellany · 11-29-2007, 09:03 PM

Quote:

Originally Posted by matthewg42

Code:

awk 'NR==2 { print $3 ; exit }'

I'll match that and raise you one....

Next thing--someone will pop in with the PERL solution.

Slokunshialgo · 11-29-2007, 09:53 PM

Want some Perl?

Code:

#!/usr/bin/perl

$file = `cat $ARGV[0]`;
@lines = split(/\n/, $file);
$line = @lines[1];
$line =~ s/^([^ ]+[ ]+[^ ]+[ ]+)([^ ]+)([ ]+.*)/$2/;
print $line;

No idea if it'll work or not, and I know it's probably highly inefficient, but it's Perl.

EDIT: Somebody pointed out I got the wrong word

jschiwal · 11-29-2007, 11:31 PM

Quote:

Originally Posted by pixellany

Code:

cat filename |sed -n '2p'|cut -d " " -nf 3

Assumes that words are delimited by exactly one space. If more than one space, add another sed to replace N spaces with one.

Not tested:

Code:

sed '/ */ /g'

Please stop doing that!
Use the form:
"sed -n '2p' filename |"

instead of
"cat filename | sed '/ */ /g' |"

There is absolutely no reason to use cat before sed or awk unless you want to add line numbers, or are using zcat with a compressed file.

IMHO, awk would be the best tool:
awk 'NR==2{ print $3 }' filename

No cat, only one program used, and extra white space is handled automatically.

Using perl would be overkill given the size of the perl shell. Sort of like going to the corner store in your Sherman tank instead of your sedan.

---

Yikes, looking back on the previous messages, I forgot the exit. Shame on me!

pixellany · 11-29-2007, 11:36 PM

I'm trying to work on my reputation as a consistent offender in the unnecessary use of cat.....

Seriously, I do that because it's sometimes easier to explain what is happening. If I'm actually writing a script, I will be more efficient---I promise!!