1ENDUTXENT(3P) POSIX Programmer's Manual ENDUTXENT(3P)
2
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.
10
12 endutxent, getutxent, getutxid, getutxline, pututxline, setutxent -
13 user accounting database functions
14
16 #include <utmpx.h>
17 void endutxent(void);
19 struct utmpx *getutxent(void);
20 struct utmpx *getutxid(const struct utmpx *id);
21 struct utmpx *getutxline(const struct utmpx *line);
22 struct utmpx *pututxline(const struct utmpx *utmpx);
23 void setutxent(void);
24
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 open
31 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 by
35 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 ut_type Member Other Members with Meaningful Data
66 EMPTY No others
68 BOOT_TIME ut_tv
69 OLD_TIME ut_tv
70 NEW_TIME ut_tv
71 USER_PROCESS ut_id, ut_user (login name of the user),
72 ut_line, ut_pid, ut_tv
73 INIT_PROCESS ut_id, ut_pid, ut_tv
74 LOGIN_PROCESS ut_id, ut_user (implementation-defined
75 name of the login process), ut_pid,
76 ut_tv
77 DEAD_PROCESS ut_id, ut_pid, ut_tv
78 An implementation that provides extended security controls may impose
80 implementation-defined restrictions on accessing the user accounting
81 database. In particular, the system may deny the existence of some or
82 all of the user accounting database entries associated with users other
83 than the caller.
84 If the process has appropriate privileges, the pututxline() function
86 shall write out the structure into the user accounting database. It
87 shall use getutxid() to search for a record that satisfies the request.
88 If this search succeeds, then the entry shall be replaced. Otherwise, a
89 new entry shall be made at the end of the user accounting 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 reentrant. A function that is not required
98 to be reentrant is not required to be thread-safe.
99
101 Upon successful completion, getutxent(), getutxid(), and getutxline()
102 shall return a pointer to a utmpx structure containing a copy of the
103 requested entry in the user accounting database. Otherwise, a null
104 pointer shall be returned.
105 The return value may point to a static area which is overwritten by a
107 subsequent call to getutxid() or getutxline().
108 Upon successful completion, pututxline() shall return a pointer to a
110 utmpx structure containing a copy of the entry added to the user
111 accounting database. Otherwise, a null pointer shall be returned.
112 The endutxent() and setutxent() functions shall not return a value.
114
116 No errors are defined for the endutxent(), getutxent(), getutxid(),
117 getutxline(), and setutxent() functions.
118 The pututxline() function may fail if:
120 EPERM The process does not have appropriate privileges.
122 The following sections are informative.
125
127 None.
128
130 The sizes of the arrays in the structure can be found using the sizeof
131 operator.
132
134 None.
135
137 None.
138
140 The Base Definitions volume of IEEE Std 1003.1-2001, <utmpx.h>
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143 Portions of this text are reprinted and reproduced in electronic form
144 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
145 -- Portable Operating System Interface (POSIX), The Open Group Base
146 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
147 Electrical and Electronics Engineers, Inc and The Open Group. In the
148 event of any discrepancy between this version and the original IEEE and
149 The Open Group Standard, the original IEEE and The Open Group Standard
150 is the referee document. The original Standard can be obtained online
151 at http://www.opengroup.org/unix/online.html .
152IEEE/The Open Group 2003 ENDUTXENT(3P)