Unmasking the User in PHP CLI Scripts

Who are you. Whoo whoo. Whoo whoo.

…The Who? Anyone? …Bueller?

So let’s say you need to know what user is running a script in PHP. If you’re like me, you may have tried get_current_user only to find that’s just for the current owner of the file. Well THAT’S deceivingly unhelpful! =\

Wait! Sec. One more moment of gripe: If what get_current_user in php does makes sense to you, I’d like to be the first to ask you: …How?!

Not only did that not help, but I also couldn’t find any solutions or hints in the right direction from the comments in the documentation (generally, I find them to be a good place for a next step). There was one suggesting to using posix functions like this: print_r(posix_getpwuid(posix_geteuid())); — however, no luck! If the user is invoking the script with sudo, we lose all trace of who done it. Also, this is technique can limit who can use it as it’s not uncommon for environments to disable posix_* functions for security.

So, Who Really Done It?!

Ranting aside… the answer to this eluded me! Low and behold, the it was inside of $_SERVER all along. Le sigh. I put together a quick function with a few fallbacks to figure it out. Let me know if this doesn’t work for you, but for me, does the trick in spades =]

I like this solution the best. Not only is this data already in the scope of our script already, but we don’t have to use posix or try crap like echo exec("who am i"); and parsing through that. #winning

Hope that helps someone out there in the ether!