getlogin - get login name
getlogin() returns a pointer to the login name as found in /etc/utmp.
It may be used in conjunction with getpwnam() to locate the correct
password file entry when the same user ID is shared by several login
If getlogin() is called within a process that is not attached to a ter-
minal, or if there is no entry in /etc/utmp for the process's terminal,
it returns a NULL pointer. The correct procedure for determining the
login name is to call cuserid(), or to call getlogin() and, if it
fails, to call getpwuid(getuid()).
cuserid(3v), getpwent(3v), utmp(5V)
getlogin() returns a pointer to the login name on success. If the name
is not found, it returns NULL.
The return values point to static data whose content is overwritten by
getlogin() does not work for processes running under a pty (for exam-
ple, emacs shell buffers, or shell tools) unless the program ``fakes''
the login name in the /etc/utmp file.
21 January 1990 GETLOGIN(3V)