The <utmpx.h> header shall define the utmpx structure that shall include at least the following members:
char ut_user User login name. char ut_id Unspecified initialization process identifier. char ut_line Device name. pid_t ut_pid Process ID. short ut_type Type of entry. struct timeval ut_tv Time entry was made.
The pid_t type shall be defined through typedef as described in <sys/types.h> .
The timeval structure shall be defined as described in <sys/time.h> .
Inclusion of the <utmpx.h> header may also make visible all symbols from <sys/time.h>.
The following symbolic constants shall be defined as possible values for the ut_type member of the utmpx structure:
- No valid user accounting information.
- Identifies time of system boot.
- Identifies time when system clock changed.
- Identifies time after system clock changed.
- Identifies a process.
- Identifies a process spawned by the init process.
- Identifies the session leader of a logged-in user.
Identifies a session leader who has exited.
The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided.
void endutxent(void); struct utmpx *getutxent(void); struct utmpx *getutxid(const struct utmpx *); struct utmpx *getutxline(const struct utmpx *); struct utmpx *pututxline(const struct utmpx *); void setutxent(void);
The following sections are informative.
COPYRIGHTPortions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .