linux - Location of cd executable

Question

I read that the executables for the commands issued using exec() calls are supposed to be stored in directories that are part of the PATH variable.

Accordingly, I found the executables for ls, chmod, grep, cat in /bin.

However, I could not find the executable for cd.

Where is it located?

Answer 1

A process can only affect its own working directory. When an executable is executed by the shell it executes as a child process, so a cd executable (if one existed) would change that child process's working directory without affecting the parent process (the shell), hence the cd command must be implemented as a shell built-in that actually executes in the shell's own process.