PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

ENDUTXENT(3P)             POSIX Programmer's Manual            ENDUTXENT(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       endutxent, getutxent, getutxid, getutxline, pututxline, setutxent —
       user accounting database functions

SYNOPSIS         top

       #include <utmpx.h>

       void endutxent(void);
       struct utmpx *getutxent(void);
       struct utmpx *getutxid(const struct utmpx *id);
       struct utmpx *getutxline(const struct utmpx *line);
       struct utmpx *pututxline(const struct utmpx *utmpx);
       void setutxent(void);

DESCRIPTION         top

       These functions shall provide access to the user accounting database.

       The getutxent() function shall read the next entry from the user
       accounting database.  If the database is not already open, it shall
       open it. If it reaches the end of the database, it shall fail.

       The getutxid() function shall search forward from the current point
       in the database.  If the ut_type value of the utmpx structure pointed
       to by id is BOOT_TIME, OLD_TIME, or NEW_TIME, then it shall stop when
       it finds an entry with a matching ut_type value. If the ut_type value
       is INIT_PROCESS, LOGIN_PROCESS, USER_PROCESS, or DEAD_PROCESS, then
       it shall stop when it finds an entry whose type is one of these four
       and whose ut_id member matches the ut_id member of the utmpx
       structure pointed to by id.  If the end of the database is reached
       without a match, getutxid() shall fail.

       The getutxline() function shall search forward from the current point
       in the database until it finds an entry of the type LOGIN_PROCESS or
       USER_PROCESS which also has a ut_line value matching that in the
       utmpx structure pointed to by line.  If the end of the database is
       reached without a match, getutxline() shall fail.

       The getutxid() or getutxline() function may cache data. For this
       reason, to use getutxline() to search for multiple occurrences, the
       application shall zero out the static data after each success, or
       getutxline() may return a pointer to the same utmpx structure.

       There is one exception to the rule about clearing the structure
       before further reads are done. The implicit read done by pututxline()
       (if it finds that it is not already at the correct place in the user
       accounting database) shall not modify the static structure returned
       by getutxent(), getutxid(), or getutxline(), if the application has
       modified this structure and passed the pointer back to pututxline().

       For all entries that match a request, the ut_type member indicates
       the type of the entry. Other members of the entry shall contain
       meaningful data based on the value of the ut_type member as follows:

 ┌───────────────┬─────────────────────────────────────────────────────────────────┐
 │ut_type Member Other Members with Meaningful Data                │
 ├───────────────┼─────────────────────────────────────────────────────────────────┤
 │EMPTY          │ No others                                                       │
 │BOOT_TIME      │ ut_tv                                                           │
 │OLD_TIME       │ ut_tv                                                           │
 │NEW_TIME       │ ut_tv                                                           │
 │USER_PROCESS   │ ut_id, ut_user (login name of the user), ut_line, ut_pid, ut_tv │
 │INIT_PROCESS   │ ut_id, ut_pid, ut_tv                                            │
 │LOGIN_PROCESS  │ ut_id, ut_user (implementation-defined name of the login        │
 │               │ process), ut_line, ut_pid, ut_tv                                │
 │DEAD_PROCESS   │ ut_id, ut_pid, ut_tv                                            │
 └───────────────┴─────────────────────────────────────────────────────────────────┘
       An implementation that provides extended security controls may impose
       implementation-defined restrictions on accessing the user accounting
       database. In particular, the system may deny the existence of some or
       all of the user accounting database entries associated with users
       other than the caller.

       If the process has appropriate privileges, the pututxline() function
       shall write out the structure into the user accounting database. It
       shall search for a record as if by getutxid() that satisfies the
       request. If this search succeeds, then the entry shall be replaced.
       Otherwise, a new entry shall be made at the end of the user
       accounting database.

       The endutxent() function shall close the user accounting database.

       The setutxent() function shall reset the input to the beginning of
       the database. This should be done before each search for a new entry
       if it is desired that the entire database be examined.

       These functions need not be thread-safe.

RETURN VALUE         top

       Upon successful completion, getutxent(), getutxid(), and getutxline()
       shall return a pointer to a utmpx structure containing a copy of the
       requested entry in the user accounting database. Otherwise, a null
       pointer shall be returned.

       The return value may point to a static area which is overwritten by a
       subsequent call to getutxid() or getutxline().

       Upon successful completion, pututxline() shall return a pointer to a
       utmpx structure containing a copy of the entry added to the user
       accounting database. Otherwise, a null pointer shall be returned.

       The endutxent() and setutxent() functions shall not return a value.

ERRORS         top

       No errors are defined for the endutxent(), getutxent(), getutxid(),
       getutxline(), and setutxent() functions.

       The pututxline() function may fail if:

       EPERM  The process does not have appropriate privileges.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       The sizes of the arrays in the structure can be found using the
       sizeof operator.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       The Base Definitions volume of POSIX.1‐2008, utmpx.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) 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.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                       ENDUTXENT(3P)