getutent
Hurricane Electric Internet Services
NAME
getutent, getutid, getutline, pututline, setutent, endu-
tent, utmpname - access utmp file entries
SYNOPSIS
#include <utmp.h>
struct utmp *getutent(void);
struct utmp *getutid(struct utmp *ut);
struct utmp *getutline(struct utmp *ut);
void pututline(struct utmp *ut);
void setutent(void);
void endutent(void);
void utmpname(const char *file);
DESCRIPTION
utmpname() sets the name of the utmp-format file for the
other utmp functions to access. If utmpname() is not used
to set the filename before the other functions are used,
they assume _PATH_UTMP, as defined in <paths.h>.
setutent() rewinds the file pointer to the beginning of
the utmp file. It is generally a Good Idea to call it
before any of the other functions.
endutent() closes the utmp file. It should be called when
the user code is done accessing the file with the other
functions.
getutent() reads a line from the current file position in
the utmp file. It returns a pointer to a structure con-
taining the fields of the line.
getutid() searches forward from the current file position
in the utmp file based upon ut. If ut->ut_type is
RUN_LVL, BOOT_TIME, NEW_TIME, or OLD_TIME, getutid() will
find the first entry whose ut_type field matches
ut->ut_type. If ut->ut_type is INIT_PROCESS, LOGIN_PRO-
CESS, USER_PROCESS, or DEAD_PROCESS, getutid() will find
the first entry whose ut_id field matches ut->ut_id.
getutline() searches forward from the current file posi-
tion in the utmp file. It scans entries whose ut_type is
USER_PROCESS or LOGIN_PROCESS and returns the first one
whose ut_line field matches ut->ut_line.
pututline() writes the utmp structure ut into the utmp
file. It uses getutid() to search for the proper place in
the file to insert the new entry. If it cannot find an
appropriate slot for ut, pututline() will append the new
entry to the end of the file.
RETURN VALUE
getutent(), getutid(), and getutline() return a pointer to
a struct utmp, which is defined in <utmp.h>.
FILES
/var/run/utmp - database of currently logged-in users
/var/log/wtmp - database of past user logins
CONFORMING TO
XPG 2, SVID 2, Linux FSSTND 1.2
SEE ALSO
utmp(5)
Hurricane Electric Internet Services
Copyright (C) 1998
Hurricane Electric.
All Rights Reserved.