Find all files matching 'name' on linux system, and search with them for 'text'

Question

I need to find all instances of \'filename.ext\' on a linux system and see which ones contain the text \'lookingfor\'.

Is there a set of linux command line operation

Answer 1

find / -type f -name filename.ext -exec grep -l 'lookingfor' {} +

Using a + to terminate the command is more efficient than \; because find sends a whole batch of files to grep instead of sending them one by one. This avoids a fork/exec for each single file which is found.

A while ago I did some testing to compare the performance of xargs vs {} + vs {} \; and I found that {} + was faster. Here are some of my results:

time find . -name "*20090430*" -exec touch {} +
real    0m31.98s
user    0m0.06s
sys     0m0.49s

time find . -name "*20090430*" | xargs touch
real    1m8.81s
user    0m0.13s
sys     0m1.07s

time find . -name "*20090430*" -exec touch {} \;
real    1m42.53s
user    0m0.17s
sys     0m2.42s