These are actually two scenarios.

If you want to return the number of times a string is found within a file you take the "-c" ("count") option of grep:

Code:

# grep -c "text" /path/to/file_with_text_in.it
2

This would mean "text" is occurring in two lines of the file. To use it in a script:

Code:

iFoundNr=$(grep -c "<searchtext>" /path/to/file)

if [ $iFoundNr -eq 0 ] ; then
     echo "<searchtext>" was not found"
else
     echo "<searchtext> was found in $iFoundNr lines"
fi

But i suspect that you created the variable just because you weren't able to imagine a simpler way. Basically you want to do one thing if the text is found (however often) and another thing if not, right? Well, here it goes: the grep utility returns an "error level", which you can use. "0" means the search text was found, different than 0 means it was not found. Because in shell programming "0" equals to "true" and non-"0" equals to "false" you can use the "-q" (quiet) option of grep to suppress all output of it and directly write:

Code:

if grep -q "<searchtext>" /path/to/file ; then
     do_found
else
     do_notfound
done

You haven't asked the question, but an additional warning: when using variable contents as search patterns for grep (or similar tools: awk, sed, ...) take into account that some characters have a special meaning (they are so-called "meta-characters). The first of the following example will work as expected, the second one won't:

Code:

# search="abcd"         # this will work
# grep "$search" /path/to/file

# search="a[bc]d"       # this will work too, but not in the expected way
# grep "$search" /path/to/file

If you want to search for the string "a[bc]d" you need to "escape" metacharacters. To make the second example working (that is: searching for the fixed string "a[bc]d") you need to do that (notice the change in quoting too):

Code:

# search='a\[bc\]d'
# grep "$search" /path/to/file

I hope this helps.

bakunin