Shell Programming and Scripting

Don, I think you mean

Code:

#!/bin/your_shell
cat "$@" | grep -F 'make'

grep reads from the pipe stream, and cannot see the file names.
It is equivalent to

Code:

grep -F -h 'make' "$@"

where grep sees the file names and the -h prevents printing them as a prefix.
Unfortunately grep by default prefixes the file names when it has got two or more file names. But not with one file name.
And there is no option to enforce the prefix. Therefore the /dev/null trick: it is one more file name. Nothing is ever found there, but it enforces the prefix. For example

Code:

grep -F 'make' /dev/null "$@"

will prefix the file name even if the "$@" has only one argument (file name).

Are {} \+ and {} + same?

Hi MadeInGermany,
Yes. I agree with all of the above. Note that the code the user posted was:

Code:

-exec cat {} | grep "make"

and I was demonstrating how to get the same output. And, I later suggested using the /dev/null trick because I assume (without any indication from the original poster of this thread) that just having a list of matching lines without knowing what files they came from would not be very useful. I should have made clear in post #7 that the discussion I included in post #3 still applied. Yes. But {} ; cannot be used instead of {} \;. The semicolon has special meaning to the shell and must be escaped to make the shell pass the semicolon to find. The plus-sign is not special to the shell in this context, so it does not need to be escaped.

Code:

find . -type f -exec grep "make" {} \;

Is it possible to get the same output with find without using -exec grep? Does find have anything to search string in files?

I don't know of any version of find that has a primary that searches file contents. And you haven't bothered to tell us what operating system you're using, so we can't check the find man page on your system to see if it has any extensions that might provide that capability. Why don't you read the find man page on your system and see if you can find any primaries or options that would do what you want with the find that is available on your system?

In addition to what DonCragun said, you could also use

Code:

grep -rF make .