How to find files with a specific pattern in the parent and child directory?

Question

How to find files with a specific pattern in the parent and child directory of my present working directory using a single command ?

Filename - test.txt, the file has the pattern nslookup

This file is present in 3 directories and they are /home, /home/1 and /home/1/2

I am currently at /home/1. I have tried below commands :

find ../ -type f -name "test.txt"

Output :

../test.txt
../home/1/test.txt
../home/1/2/test.txt

I was able to find the files, hence I tried the below command :

$ find ../ -type f -exec grep "nslookup" {} \;
nslookup
nslookup
nslookup

This doesn't display the file names.

Command :

find . -type f -name "test.txt" | xargs grep "nslookup"

==> gives me files in pwd and child directories :

./1/test.txt:nslookup
./test.txt:nslookup

but when I try to search in the parent directory as shown below the results are erroneous :

find ../ -type f -name "test.txt" | xargs grep "nslookup"

User@User-PC ~/test
$ uname -a
CYGWIN_NT-6.1 User-PC 2.5.2(0.297/5/3) 2016-06-23 14:29 x86_64 Cygwin

Answer 1

Your command

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

is almost correct, apart from the fact that grep by default does not display the filename when it is given only a single file to work with.

Here are two ways of fixing this:

1. Using a grep that has the non-standard (but common) -H option to always display the filename:

   find ../ -type f -exec grep -H 'nslookup' {} \;
   

2. Giving grep at least two filenames:

   find ../ -type f -exec grep 'nslookup' /dev/null {} \;
   

If you are interested in only the filenames, then these are two ways of doing this:

1. Use the standard -l option with grep:

   find ../ -type f -exec grep -l 'nslookup' {} \;
   

2. Let find output the pathname of the file if it contains a match:

   find ../ -type f -exec grep -q 'nslookup' {} \; -print
   

   Here, we only use grep to detect if the pattern matches. Its -q option stops it from outputting anything and find will use the exit status of the utility to determine whether to do the -print action or not.