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.TH POSIX_TRACE_CLOSE "3P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual"

.SH 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.

.SH NAME

posix_trace_close,

posix_trace_open,

posix_trace_rewind

\(em trace log management

(\fBTRACING\fP)

.SH SYNOPSIS

.LP

.nf

#include <trace.h>

.P

int posix_trace_close(trace_id_t \fItrid\fP);

int posix_trace_open(int \fIfile_desc\fP, trace_id_t *\fItrid\fP);

int posix_trace_rewind(trace_id_t \fItrid\fP);

.fi

.SH DESCRIPTION

The

\fIposix_trace_close\fR()

function shall deallocate the trace log identifier indicated by

.IR trid ,

and all of its associated resources. If there is no valid trace log

pointed to by the

.IR trid ,

this function shall fail.

.P

The

\fIposix_trace_open\fR()

function shall allocate the necessary resources and establish the

connection between a trace log identified by the

.IR file_desc

argument and a trace stream identifier identified by the object pointed

to by the

.IR trid

argument. The

.IR file_desc

argument should be a valid open file descriptor that corresponds to a

trace log. The

.IR file_desc

argument shall be open for reading. The current trace event timestamp,

which specifies the timestamp of the trace event that will be read by

the next call to

\fIposix_trace_getnext_event\fR(),

shall be set to the timestamp of the oldest trace event recorded in the

trace log identified by

.IR trid .

.P

The

\fIposix_trace_open\fR()

function shall return a trace stream identifier in the variable

pointed to by the

.IR trid

argument, that may only be used by the following functions:

.TS

tab(!);

l l.

T{

.nf

\fIposix_trace_close\fR()

\fIposix_trace_eventid_equal\fR()

\fIposix_trace_eventid_get_name\fR()

\fIposix_trace_eventtypelist_getnext_id\fR()

\fIposix_trace_eventtypelist_rewind\fR()

T}!T{

.nf

\fIposix_trace_get_attr\fR()

\fIposix_trace_get_status\fR()

\fIposix_trace_getnext_event\fR()

\fIposix_trace_rewind\fR()

.fi

T}

.TE

.P

In particular, notice that the operations normally used by a trace

controller process, such as

\fIposix_trace_start\fR(),

\fIposix_trace_stop\fR(),

or

\fIposix_trace_shutdown\fR(),

cannot be invoked using the trace stream identifier returned by the

\fIposix_trace_open\fR()

function.

.P

The

\fIposix_trace_rewind\fR()

function shall reset the current trace event timestamp, which specifies

the timestamp of the trace event that will be read by the next call to

\fIposix_trace_getnext_event\fR(),

to the timestamp of the oldest trace event recorded in the trace log

identified by

.IR trid .

.SH "RETURN VALUE"

Upon successful completion, these functions shall return a value of

zero. Otherwise, they shall return the corresponding error number.

.P

If successful, the

\fIposix_trace_open\fR()

function stores the trace stream identifier value in the object pointed

to by

.IR trid .

.SH ERRORS

The

\fIposix_trace_open\fR()

function shall fail if:

.TP

.BR EINTR

The operation was interrupted by a signal and thus no trace log was

opened.

.TP

.BR EINVAL

The object pointed to by

.IR file_desc

does not correspond to a valid trace log.

.br

.P

The

\fIposix_trace_close\fR()

and

\fIposix_trace_rewind\fR()

functions may fail if:

.TP

.BR EINVAL

The object pointed to by

.IR trid

does not correspond to a valid trace log.

.LP

.IR "The following sections are informative."

.SH EXAMPLES

None.

.SH "APPLICATION USAGE"

None.

.SH RATIONALE

None.

.SH "FUTURE DIRECTIONS"

The

\fIposix_trace_close\fR(),

\fIposix_trace_open\fR(),

and

\fIposix_trace_rewind\fR()

functions may be removed in a future version.

.SH "SEE ALSO"

.ad l

.IR "\fIposix_trace_get_attr\fR\^(\|)",

.IR "\fIposix_trace_get_filter\fR\^(\|)",

.IR "\fIposix_trace_getnext_event\fR\^(\|)"

.ad b

.P

The Base Definitions volume of POSIX.1\(hy2008,

.IR "\fB<trace.h>\fP"

.SH COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form

from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology

-- Portable Operating System Interface (POSIX), The Open Group Base

Specifications Issue 7, Copyright (C) 2013 by the Institute of

Electrical and Electronics Engineers, Inc and The Open Group.

(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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.unix.org/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 .