Shell Programming and Scripting

Is there a way for grep to output only the found string and not the whole line?

I have a ksh script which reads in a file and loops through every line looking up on a grep -f list. For it to only display only the string found i pass this to awk as a variable and loop through the list file using match and print the list line with the string found.

Can this be done any simpler using ksh?

Thanks

Ste

See if you have the -o flag for grep. If yes use

Code:

grep -o "needle" haystack

If no, try sed.

Code:

sed -n -e "s/.*\(needle\).*/\1/p" haystack

Code:

grep -f list file | sed "s/ /\\
/g" > tmp
grep -f tmp list

if there is no -o option available with grep

Code:

grep needle haystack 2>/dev/null
if [ $? -eq 0 ]
then
  echo needle
fi

thanks for the quick replies,

we don't have the "grep -o" option, the answer which works best for my needs is:

sed -n -e "s/.*\(needle\).*/\1/p" haystack

Again thanks for all the replies,

Ste

Since you only want to know if the string is there:

grep "string" file > /dev/null && echo "string"