linux system call for user_logins

[dalgin]

I am trying to figure out what the system call is when user logins into a linux system.
basically what is the function that is callled when user logs in.
thanks

 

[Noriaki]

Probably get more help over in the OS forum.

There are some guys over there that are really knowledgable about the detailed underpinnings of *nix.

 

[Cogman]

I dont know what it is, but you can get to the login console by using exit and you can switch users by using root. the issue file in the ect folder has the message that is displayed when you start up. hope this helps

 

[SlimHarpo]

If you're just looking for how a process changes its uid, then look at "man setuid", and the referenced man pages from there.

Otherwise, read "man login" for a description of what happens when a user logs in. There isn't any single "login()" system call or anything like that; instead, there are a whole slew of system calls made by agetty or the like, the login program, and then by the user's shell. If you are interested in a particular part of the login process, then try to be more specific, or use strace to attach to an instance of agetty (you'll need to be root), and watch for yourself.