Environment: Mac OSX 10.10. When I was trying to use gitk, it shows:
Coda-2:~ Coda$ gitk
-bash: gitk: command not found
I thin
Granted the OP is using Mac, a Linux user will find this link from Google and the accepted solution will not help.
On Linux, use your favourite package manager and install git-gui.
On RedHat-based systems, ex CentOS, do:
yum install -y git-gui
which will install the gitk dependency.
Done.
Follow these steps to fix the issue:
Check git version with git --version, and it may show old version.
Update Homebrew with brew update.
Install the latest version of Git from Homebrew with brew install git.
(Note that if anything went wrong with the installation, the brew doctor command can be used. In my case, it told me to use brew link git.)
I can now use gitk.
I just installed the latest version of git via homebrew on macos.
11:28 $ git --version
git version 2.25.0
It doesn't seem to have gitk and git gui so I noticed the answer for linux and tried to install the same package git-gui via homebrew and it worked.
brew install git-gui
Found the bug here.
I'm running macos 10.14.5 Mojave.