NAME

getlogin() − get login name

SYNOPSIS

#include <unistd.h>

char *getlogin(void);

DESCRIPTION

getlogin() returns a pointer to the login name as found in /etc/utmp.  It can be used in conjunction with getpwnam() to locate the correct password file entry when the same user ID is shared by several login names. 

If getlogin() is called within a process that is not attached to a terminal, it returns a NULL pointer.  The recommended procedure to obtain the user name associated with the real user ID of the calling process is to call getlogin(), and if that fails to call getpwuid().  The function cuserid() can be used to obtain the user name associated with the effective user ID of the calling process. 

ERRORS

getlogin() fails if any of the following is true:

[EBADF] An invalid file descriptor was obtained. 

[EMFILE] Too many file descriptors are in use by this process. 

[ENFILE] The system file table is full. 

FILES

/etc/utmp

SEE ALSO

getgrent(3C), getpwent(3C), cuserid(3S), utmp(4). 

DIAGNOSTICS

getlogin() returns the NULL pointer if name is not found. 

WARNINGS

Return values point to static data whose content is overwritten by each call. 

STANDARDS CONFORMANCE

getlogin(): AES, SVID2, XPG2, XPG3, XPG4, FIPS 151-2, POSIX.1

Hewlett-Packard Company  —  HP-UX Release 9.0: August 1992