ack is a command-line utility written in Perl for searching strings inside files. By default when you search, it shows you the file name along with the matching content of the file. Sometimes you may only want to list file names that match your search. This can be done with -l option
ack -l "search string here"
Example
See ack
ack is a tool like grep optimized for programmers.
ack show the matched files name only
On Debian/Ubuntu, you can install it with apt
apt install ack
To install from source, run
curl https://beyondgrep.com/ack-v3.0.2 > /usr/local/bin/ack && chmod 0755 /usr/local/bin/ack
For installing for just one user, run
curl https://beyondgrep.com/ack-v3.0.2 > ~/bin/ack && chmod 0755 ~/bin/ack
On RHEL/CentOS, you may need to install dependency
yum install perl-version
For the latest version, always check
https://beyondgrep.com/install/
See grep