What is the path to the global directory for binary files in MacOS? What is the path to the global directory (for example: /usr/local/bin etc.) for binary files in macOS?

The problem is that I can run the command from another user. With this command I want to start the Caddy web-server: su _www -c caddy

I know where this file is located. The problem is that Caddy can only work with php socket if the Caddy process is run as user _www. But if I switch to _www user (this is not a problem), I can not start the process, because the Caddy file is in the PATH of another user.

Of course I can send the file to another user to run, but this is too long and inconvenient process. I just need to start the process from the right user. In Ubuntu, such a problem is not surprising.

OS: MacOS High Sierra 10.13.1
The problem is solved. It was enough to put a binary file Caddy in the directory: /usr/local/bin

If the binary file is in the directory /usr/local/bin, Caddy available for reading for user _www