1ENDUTXENT(P) POSIX Programmer's Manual ENDUTXENT(P)
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6 endutxent, getutxent, getutxid, getutxline, pututxline, setutxent -
7 user accounting database functions
8
10 #include <utmpx.h>
11 void endutxent(void);
13 struct utmpx *getutxent(void);
14 struct utmpx *getutxid(const struct utmpx *id);
15 struct utmpx *getutxline(const struct utmpx *line);
16 struct utmpx *pututxline(const struct utmpx *utmpx);
17 void setutxent(void);
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21 These functions shall provide access to the user accounting database.
22 The getutxent() function shall read the next entry from the user
24 accounting database. If the database is not already open, it shall open
25 it. If it reaches the end of the database, it shall fail.
26 The getutxid() function shall search forward from the current point in
28 the database. If the ut_type value of the utmpx structure pointed to by
29 id is BOOT_TIME, OLD_TIME, or NEW_TIME, then it shall stop when it
30 finds an entry with a matching ut_type value. If the ut_type value is
31 INIT_PROCESS, LOGIN_PROCESS, USER_PROCESS, or DEAD_PROCESS, then it
32 shall stop when it finds an entry whose type is one of these four and
33 whose ut_id member matches the ut_id member of the utmpx structure
34 pointed to by id. If the end of the database is reached without a
35 match, getutxid() shall fail.
36 The getutxline() function shall search forward from the current point
38 in the database until it finds an entry of the type LOGIN_PROCESS or
39 USER_PROCESS which also has a ut_line value matching that in the utmpx
40 structure pointed to by line. If the end of the database is reached
41 without a match, getutxline() shall fail.
42 The getutxid() or getutxline() function may cache data. For this rea‐
44 son, to use getutxline() to search for multiple occurrences, the appli‐
45 cation shall zero out the static data after each success, or getutx‐
46 line() may return a pointer to the same utmpx structure.
47 There is one exception to the rule about clearing the structure before
49 further reads are done. The implicit read done by pututxline() (if it
50 finds that it is not already at the correct place in the user account‐
51 ing database) shall not modify the static structure returned by getutx‐
52 ent(), getutxid(), or getutxline(), if the application has modified
53 this structure and passed the pointer back to pututxline().
54 For all entries that match a request, the ut_type member indicates the
56 type of the entry. Other members of the entry shall contain meaningful
57 data based on the value of the ut_type member as follows:
58 ut_type Member Other Members with Meaningful Data
60 EMPTY No others
61 BOOT_TIME ut_tv
62 OLD_TIME ut_tv
63 NEW_TIME ut_tv
64 USER_PROCESS ut_id, ut_user (login name of the user),
65 ut_line, ut_pid, ut_tv
66 INIT_PROCESS ut_id, ut_pid, ut_tv
68 LOGIN_PROCESS ut_id, ut_user (implementation-defined
69 name of the login process), ut_pid,
70 ut_tv
71 DEAD_PROCESS ut_id, ut_pid, ut_tv
72 An implementation that provides extended security controls may impose
74 implementation-defined restrictions on accessing the user accounting
75 database. In particular, the system may deny the existence of some or
76 all of the user accounting database entries associated with users other
77 than the caller.
78 If the process has appropriate privileges, the pututxline() function
80 shall write out the structure into the user accounting database. It
81 shall use getutxid() to search for a record that satisfies the request.
82 If this search succeeds, then the entry shall be replaced. Otherwise, a
83 new entry shall be made at the end of the user accounting database.
84 The endutxent() function shall close the user accounting database.
86 The setutxent() function shall reset the input to the beginning of the
88 database. This should be done before each search for a new entry if it
89 is desired that the entire database be examined.
90 These functions need not be reentrant. A function that is not required
92 to be reentrant is not required to be thread-safe.
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95 Upon successful completion, getutxent(), getutxid(), and getutxline()
96 shall return a pointer to a utmpx structure containing a copy of the
97 requested entry in the user accounting database. Otherwise, a null
98 pointer shall be returned.
99 The return value may point to a static area which is overwritten by a
101 subsequent call to getutxid() or getutxline().
102 Upon successful completion, pututxline() shall return a pointer to a
104 utmpx structure containing a copy of the entry added to the user
105 accounting database. Otherwise, a null pointer shall be returned.
106 The endutxent() and setutxent() functions shall not return a value.
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110 No errors are defined for the endutxent(), getutxent(), getutxid(),
111 getutxline(), and setutxent() functions.
112 The pututxline() function may fail if:
114 EPERM The process does not have appropriate privileges.
116 The following sections are informative.
119
121 None.
122
124 The sizes of the arrays in the structure can be found using the sizeof
125 operator.
126
128 None.
129
131 None.
132
134 The Base Definitions volume of IEEE Std 1003.1-2001, <utmpx.h>
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137 Portions of this text are reprinted and reproduced in electronic form
138 from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
139 -- Portable Operating System Interface (POSIX), The Open Group Base
140 Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
141 Electrical and Electronics Engineers, Inc and The Open Group. In the
142 event of any discrepancy between this version and the original IEEE and
143 The Open Group Standard, the original IEEE and The Open Group Standard
144 is the referee document. The original Standard can be obtained online
145 at http://www.opengroup.org/unix/online.html .
146IEEE/The Open Group 2003 ENDUTXENT(P)