1ENDUTXENT(3P) POSIX Programmer's Manual ENDUTXENT(3P)
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6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
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13 endutxent, getutxent, getutxid, getutxline, pututxline, setutxent —
14 user accounting database functions
15
17 #include <utmpx.h>
18 void endutxent(void);
20 struct utmpx *getutxent(void);
21 struct utmpx *getutxid(const struct utmpx *id);
22 struct utmpx *getutxline(const struct utmpx *line);
23 struct utmpx *pututxline(const struct utmpx *utmpx);
24 void setutxent(void);
25
27 These functions shall provide access to the user accounting database.
28 The getutxent() function shall read the next entry from the user
30 accounting database. If the database is not already open, it shall
31 open it. If it reaches the end of the database, it shall fail.
32 The getutxid() function shall search forward from the current point in
34 the database. If the ut_type value of the utmpx structure pointed to
35 by id is BOOT_TIME, OLD_TIME, or NEW_TIME, then it shall stop when it
36 finds an entry with a matching ut_type value. If the ut_type value is
37 INIT_PROCESS, LOGIN_PROCESS, USER_PROCESS, or DEAD_PROCESS, then it
38 shall stop when it finds an entry whose type is one of these four and
39 whose ut_id member matches the ut_id member of the utmpx structure
40 pointed to by id. If the end of the database is reached without a
41 match, getutxid() shall fail.
42 The getutxline() function shall search forward from the current point
44 in the database until it finds an entry of the type LOGIN_PROCESS or
45 USER_PROCESS which also has a ut_line value matching that in the utmpx
46 structure pointed to by line. If the end of the database is reached
47 without a match, getutxline() shall fail.
48 The getutxid() or getutxline() function may cache data. For this rea‐
50 son, to use getutxline() to search for multiple occurrences, the appli‐
51 cation shall zero out the static data after each success, or getutx‐
52 line() may return a pointer to the same utmpx structure.
53 There is one exception to the rule about clearing the structure before
55 further reads are done. The implicit read done by pututxline() (if it
56 finds that it is not already at the correct place in the user account‐
57 ing database) shall not modify the static structure returned by getutx‐
58 ent(), getutxid(), or getutxline(), if the application has modified
59 this structure and passed the pointer back to pututxline().
60 For all entries that match a request, the ut_type member indicates the
62 type of the entry. Other members of the entry shall contain meaningful
63 data based on the value of the ut_type member as follows:
64 ┌───────────────┬─────────────────────────────────────────────────────────────────┐
66 │ut_type Member │ Other Members with Meaningful Data │
67 ├───────────────┼─────────────────────────────────────────────────────────────────┤
68 │EMPTY │ No others │
69 │BOOT_TIME │ ut_tv │
70 │OLD_TIME │ ut_tv │
71 │NEW_TIME │ ut_tv │
72 │USER_PROCESS │ ut_id, ut_user (login name of the user), ut_line, ut_pid, ut_tv │
73 │INIT_PROCESS │ ut_id, ut_pid, ut_tv │
74 │LOGIN_PROCESS │ ut_id, ut_user (implementation-defined name of the login │
75 │ │ process), ut_line, ut_pid, ut_tv │
76 │DEAD_PROCESS │ ut_id, ut_pid, ut_tv │
77 └───────────────┴─────────────────────────────────────────────────────────────────┘
78 An implementation that provides extended security controls may impose
79 implementation-defined restrictions on accessing the user accounting
80 database. In particular, the system may deny the existence of some or
81 all of the user accounting database entries associated with users other
82 than the caller.
83 If the process has appropriate privileges, the pututxline() function
85 shall write out the structure into the user accounting database. It
86 shall search for a record as if by getutxid() that satisfies the
87 request. If this search succeeds, then the entry shall be replaced.
88 Otherwise, a new entry shall be made at the end of the user accounting
89 database.
90 The endutxent() function shall close the user accounting database.
92 The setutxent() function shall reset the input to the beginning of the
94 database. This should be done before each search for a new entry if it
95 is desired that the entire database be examined.
96 These functions need not be thread-safe.
98
100 Upon successful completion, getutxent(), getutxid(), and getutxline()
101 shall return a pointer to a utmpx structure containing a copy of the
102 requested entry in the user accounting database. Otherwise, a null
103 pointer shall be returned.
104 The return value may point to a static area which is overwritten by a
106 subsequent call to getutxid() or getutxline().
107 Upon successful completion, pututxline() shall return a pointer to a
109 utmpx structure containing a copy of the entry added to the user
110 accounting database. Otherwise, a null pointer shall be returned.
111 The endutxent() and setutxent() functions shall not return a value.
113
115 No errors are defined for the endutxent(), getutxent(), getutxid(),
116 getutxline(), and setutxent() functions.
117 The pututxline() function may fail if:
119 EPERM The process does not have appropriate privileges.
121 The following sections are informative.
123
125 None.
126
128 The sizes of the arrays in the structure can be found using the sizeof
129 operator.
130
132 None.
133
135 None.
136
138 The Base Definitions volume of POSIX.1‐2008, <utmpx.h>
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141 Portions of this text are reprinted and reproduced in electronic form
142 from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
143 -- Portable Operating System Interface (POSIX), The Open Group Base
144 Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
145 cal and Electronics Engineers, Inc and The Open Group. (This is
146 POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
147 event of any discrepancy between this version and the original IEEE and
148 The Open Group Standard, the original IEEE and The Open Group Standard
149 is the referee document. The original Standard can be obtained online
150 at http://www.unix.org/online.html .
151 Any typographical or formatting errors that appear in this page are
153 most likely to have been introduced during the conversion of the source
154 files to man page format. To report such errors, see https://www.ker‐
155 nel.org/doc/man-pages/reporting_bugs.html .
156IEEE/The Open Group 2013 ENDUTXENT(3P)