Shell Programming and Scripting

I need to get the line number for a line, but I don't know where the file the line will appear.

The line is always constant, but appears in different places.

ie

abc
bcd
cde
fff
aaa
bbb
ccc
ddd

and I would need the line number for fff, any help on this would be greatly appreciated.

Code:

cat test.txt | perl -ne 'print "$.\n" if $_ eq "fff\n"'

There are several variations on this you can use, but this should work.

If you prefer a regex, or don't care if the line match is inexact, you can do it this way:

Code:

cat test.txt | perl -ne 'print "$.\n" if $_ =~ /fff/'

This way, you don't need to specify the \n.

Here's a more explicit version:

Code:

cat test.txt | perl -ne 'print "$.\n" if $_ =~ /^fff$/'

The ^ indicates the beginning of the line, and the $ indicates the end of the line. So this will match it only if "fff" is the entire content of the line. If you want it to be case-insensitive, add "i" after the final backslash:

Code:

cat test.txt | perl -ne 'print "$.\n" if $_ =~ /^fff$/i'

Many ways, couple follow:

Code:

#  grep -n fff infile | cut -d: -f1

Code:

awk '$0~"fff"{print NR}' infile

(use nawk or /usr/xpg4/bin/awk on solaris)

or just:

Code:

# awk '/fff/{print NR}' infile