POSIX_TRACE_CLEAR(3P)

PROLOG
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
posix_trace_clear — clear trace stream and trace log (TRACING)

SYNOPSIS

#include <sys/types.h>
#include <trace.h>

int posix_trace_clear(trace_id_t trid);

DESCRIPTION
The posix_trace_clear() function shall reinitialize the trace stream identified by the argument trid as if it were returning from the posix_trace_create() function, except that the same allocated resources shall be reused, the mapping of trace event type identifiers to trace event names shall be unchanged, and the trace stream status shall remain unchanged (that is, if it was running, it remains running and if it was suspended, it remains suspended).

All trace events in the trace stream recorded before the call to posix_trace_clear() shall be lost. The posix_stream_full_status status shall be set to POSIX_TRACE_NOT_FULL. There is no guarantee that all trace events that occurred during the posix_trace_clear() call are recorded; the behavior with respect to trace points that may occur during this call is unspecified.

If the Trace Log option is supported and the trace stream has been created with a log, the posix_trace_clear() function shall reinitialize the trace stream with the same behavior as if the trace stream was created without the log, plus it shall reinitialize the trace log associated with the trace stream identified by the argument trid as if it were returning from the posix_trace_create_withlog() function, except that the same allocated resources, for the trace log, may be reused and the associated trace stream status remains unchanged. The first trace event recorded in the trace log after the call to posix_trace_clear() shall be the same as the first trace event recorded in the active trace stream after the call to posix_trace_clear(). The posix_log_full_status status shall be set to POSIX_TRACE_NOT_FULL. There is no guarantee that all trace events that occurred during the posix_trace_clear() call are recorded in the trace log; the behavior with respect to trace points that may occur during this call is unspecified. If the log full policy is POSIX_TRACE_APPEND, the effect of a call to this function is unspecified for the trace log associated with the trace stream identified by the trid argument.

RETURN VALUE
Upon successful completion, the posix_trace_clear() function shall return a value of zero. Otherwise, it shall return the corresponding error number.

ERRORS
The posix_trace_clear() function shall fail if:

EINVAL
    The value of the trid argument does not correspond to an active trace stream.

The following sections are informative.

EXAMPLES
None.

APPLICATION USAGE
None.

RATIONALE
None.

FUTURE DIRECTIONS
The posix_trace_clear() function may be removed in a future version.

SEE ALSO
posix_trace_attr_destroy(), posix_trace_create(), posix_trace_get_attr()

The Base Definitions volume of POSIX.1-2017, <sys_types.h>, <trace.h>

COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/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 .