1POSIX_TRACE_ATTR_GETINHERITEPDO(S3IPX)Programmer'sPMOaSnIuXa_lTRACE_ATTR_GETINHERITED(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 posix_trace_attr_getinherited, posix_trace_attr_getlogfullpolicy,
13 posix_trace_attr_getstreamfullpolicy, posix_trace_attr_setinherited,
14 posix_trace_attr_setlogfullpolicy, posix_trace_attr_setstreamfullpolicy
15 — retrieve and set the behavior of a trace stream (TRACING)
16
18 #include <trace.h>
19 int posix_trace_attr_getinherited(const trace_attr_t *restrict attr,
21 int *restrict inheritancepolicy);
22 int posix_trace_attr_getlogfullpolicy(const trace_attr_t *restrict attr,
23 int *restrict logpolicy);
24 int posix_trace_attr_getstreamfullpolicy(const trace_attr_t *restrict
25 attr, int *restrict streampolicy);
26 int posix_trace_attr_setinherited(trace_attr_t *attr,
27 int inheritancepolicy);
28 int posix_trace_attr_setlogfullpolicy(trace_attr_t *attr,
29 int logpolicy);
30 int posix_trace_attr_setstreamfullpolicy(trace_attr_t *attr,
31 int streampolicy);
32
34 The posix_trace_attr_getinherited() and posix_trace_attr_setinherited()
35 functions, respectively, shall get and set the inheritance policy
36 stored in the inheritance attribute for traced processes across the
37 fork() and spawn() operations. The inheritance attribute of the
38 attributes object pointed to by the attr argument shall be set to one
39 of the following values defined by manifest constants in the <trace.h>
40 header:
41 POSIX_TRACE_CLOSE_FOR_CHILD
43 After a fork() or spawn() operation, the child shall not be
44 traced, and tracing of the parent shall continue.
45 POSIX_TRACE_INHERITED
47 After a fork() or spawn() operation, if the parent is being
48 traced, its child shall be concurrently traced using the same
49 trace stream.
50 The default value for the inheritance attribute is
52 POSIX_TRACE_CLOSE_FOR_CHILD.
53 The posix_trace_attr_getlogfullpolicy() and posix_trace_attr_setlog‐
55 fullpolicy() functions, respectively, shall get and set the trace log
56 full policy stored in the log-full-policy attribute of the attributes
57 object pointed to by the attr argument.
58 The log-full-policy attribute shall be set to one of the following val‐
60 ues defined by manifest constants in the <trace.h> header:
61 POSIX_TRACE_LOOP
63 The trace log shall loop until the associated trace stream is
64 stopped. This policy means that when the trace log gets full,
65 the file system shall reuse the resources allocated to the oldest
66 trace events that were recorded. In this way, the trace log will
67 always contain the most recent trace events flushed.
68 POSIX_TRACE_UNTIL_FULL
70 The trace stream shall be flushed to the trace log until the
71 trace log is full. This condition can be deduced from the
72 posix_log_full_status member status (see the posix_trace_sta‐
73 tus_info structure defined in <trace.h>). The last recorded
74 trace event shall be the POSIX_TRACE_STOP trace event.
75 POSIX_TRACE_APPEND
77 The associated trace stream shall be flushed to the trace log
78 without log size limitation. If the application specifies
79 POSIX_TRACE_APPEND, the implementation shall ignore the log-max-
80 size attribute.
81 The default value for the log-full-policy attribute is
83 POSIX_TRACE_LOOP.
84 The posix_trace_attr_getstreamfullpolicy() and posix_trace_attr_set‐
86 streamfullpolicy() functions, respectively, shall get and set the trace
87 stream full policy stored in the stream-full-policy attribute of the
88 attributes object pointed to by the attr argument.
89 The stream-full-policy attribute shall be set to one of the following
91 values defined by manifest constants in the <trace.h> header:
92 POSIX_TRACE_LOOP
94 The trace stream shall loop until explicitly stopped by the
95 posix_trace_stop() function. This policy means that when the
96 trace stream is full, the trace system shall reuse the resources
97 allocated to the oldest trace events recorded. In this way, the
98 trace stream will always contain the most recent trace events
99 recorded.
100 POSIX_TRACE_UNTIL_FULL
102 The trace stream will run until the trace stream resources are
103 exhausted. Then the trace stream will stop. This condition can be
104 deduced from posix_stream_status and posix_stream_full_status
105 (see the posix_trace_status_info structure defined in <trace.h>).
106 When this trace stream is read, a POSIX_TRACE_STOP trace event
107 shall be reported after reporting the last recorded trace event.
108 The trace system shall reuse the resources allocated to any trace
109 events already reported—see the posix_trace_getnext_event(),
110 posix_trace_trygetnext_event(), and posix_trace_timedget‐
111 next_event() functions—or already flushed for an active trace
112 stream with log if the Trace Log option is supported; see the
113 posix_trace_flush() function. The trace system shall restart the
114 trace stream when it is empty and may restart it sooner. A
115 POSIX_TRACE_START trace event shall be reported before reporting
116 the next recorded trace event.
117 POSIX_TRACE_FLUSH
119 If the Trace Log option is supported, this policy is identical to
120 the POSIX_TRACE_UNTIL_FULL trace stream full policy except that
121 the trace stream shall be flushed regularly as if
122 posix_trace_flush() had been explicitly called. Defining this
123 policy for an active trace stream without log shall be invalid.
124 The default value for the stream-full-policy attribute shall be
126 POSIX_TRACE_LOOP for an active trace stream without log.
127 If the Trace Log option is supported, the default value for the stream-
129 full-policy attribute shall be POSIX_TRACE_FLUSH for an active trace
130 stream with log.
131
133 Upon successful completion, these functions shall return a value of
134 zero. Otherwise, they shall return the corresponding error number.
135 If successful, the posix_trace_attr_getinherited() function shall store
137 the inheritance attribute value in the object pointed to by inheritan‐
138 cepolicy. Otherwise, the content of this object is undefined.
139 If successful, the posix_trace_attr_getlogfullpolicy() function shall
141 store the log-full-policy attribute value in the object pointed to by
142 logpolicy. Otherwise, the content of this object is undefined.
143 If successful, the posix_trace_attr_getstreamfullpolicy() function
145 shall store the stream-full-policy attribute value in the object
146 pointed to by streampolicy. Otherwise, the content of this object is
147 undefined.
148
150 These functions may fail if:
151 EINVAL The value specified by at least one of the arguments is invalid.
153 The following sections are informative.
155
157 None.
158
160 None.
161
163 None.
164
166 The following functions:
167 posix_trace_attr_getinherited()
169 posix_trace_attr_getlogfullpolicy()
170 posix_trace_attr_getstreamfullpolicy()
171 posix_trace_attr_setinherited()
172 posix_trace_attr_setlogfullpolicy()
173 posix_trace_attr_setstreamfullpolicy()
174 may be removed in a future version.
176
178 fork(), posix_trace_attr_destroy(), posix_trace_create(),
179 posix_trace_get_attr(), posix_trace_getnext_event(),
180 posix_trace_start()
181 The Base Definitions volume of POSIX.1‐2017, <trace.h>
183
185 Portions of this text are reprinted and reproduced in electronic form
186 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
187 table Operating System Interface (POSIX), The Open Group Base Specifi‐
188 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
189 Electrical and Electronics Engineers, Inc and The Open Group. In the
190 event of any discrepancy between this version and the original IEEE and
191 The Open Group Standard, the original IEEE and The Open Group Standard
192 is the referee document. The original Standard can be obtained online
193 at http://www.opengroup.org/unix/online.html .
194 Any typographical or formatting errors that appear in this page are
196 most likely to have been introduced during the conversion of the source
197 files to man page format. To report such errors, see https://www.ker‐
198 nel.org/doc/man-pages/reporting_bugs.html .
199IEEE/The Open Group 2017 POSIX_TRACE_ATTR_GETINHERITED(3P)