How can I grep in source files for some text?

Question

At the moment I'm using two commands, I'm sure there must be a better way...

wim@wim-acer:~/ffmpeg$ find . -name "*.h" -print0 | xargs -0 grep -i invalid\ preset
wim@wim-acer:~/ffmpeg$ find . -name "*.c" -print0 | xargs -0 grep -i invalid\ preset

Answer 1

ack (or, on Debian/Ubuntu, ack-grep) will ignore non-source files like version control or binaries. Very useful.

to search just .c and .h files, as above:

ack-grep -i --cc "invalid preset"

the --cc (the longer form is --type cc) only looks at .c .h & .xs files. The full list of filetypes is viewable with ack-grep --help type. Most of the time, you won't particularly need the --type, as it will generally only have the files to search, and then files you won't see by default, like binaries, backups and version control files.

Answer 2

The find command can call grep itself.

find . \( -name "*.c" -o -name "*.h" \) -exec grep -i "invalid preset" {} \; -print

and variations of thereof.

Answer 3

The grep program itself can search recursively and also accepts an option to search only certain files. The following is equivalent to your two find commands.

grep -Ri --include=*.[ch] invalid\ preset .