reading a file

pdklinux79 · 06-19-2008, 05:19 PM

how to get total number of lines in a file
how to read a particular line, eg line 7 in that file.

amani · 06-19-2008, 05:28 PM

less will provide line numbers. You just need to grep what you want.
Or you can use cat and grep.
Or vim

Best

A. Mani

bsdunix · 06-19-2008, 05:42 PM

You can use wc for number lines:
WC
http://www.linuxmanpages.com/man1/wc.1.php

and sed to show line number:
HANDY ONE-LINERS FOR SED
http://www.linuxhowtos.org/System/se...m?ref=news.rdf

and there's probably other ways to do the same thing, that's the beauty of *nix.

osor · 06-19-2008, 06:05 PM

Quote:

Originally Posted by bsdunix

and there's probably other ways to do the same thing, that's the beauty of *nix.

Here’s a few ways to show a particular line of a file (in these examples, show line 42):

Code:

awk 'NR==42' filename

Code:

sed -n '42p' filename

Code:

head -42 filename | tail -1

osor · 06-19-2008, 06:06 PM

Btw, the GNU version of cat will number lines for you:

Code:

cat -n filename

LlNUX · 06-20-2008, 12:36 AM

>how to get total number of lines in a file
Check Linux commands for wc command and/or nl command or above mention cat command.
or use vim editor

>how to read a particular line, eg line 7 in that file.

this depends on how you want to approach this problem. You can use vim editor again or you can use tail and head commands which is not really nice solution or you can write Perl script to do it.

Hope this helps