.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved 
.TH "POSIX_TRACE_EVENTID_EQUAL" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" posix_trace_eventid_equal 
.SH NAME
posix_trace_eventid_equal, posix_trace_eventid_get_name, posix_trace_trid_eventid_open
\- manipulate the trace event
type identifier (\fBTRACING\fP)
.SH SYNOPSIS
.LP
\fB#include <trace.h>
.br
.sp
int posix_trace_eventid_equal(trace_id_t\fP \fItrid\fP\fB, trace_event_id_t\fP
\fIevent1\fP\fB,
.br
\ \ \ \ \ \  trace_event_id_t\fP \fIevent2\fP\fB);
.br
int posix_trace_eventid_get_name(trace_id_t\fP \fItrid\fP\fB,
.br
\ \ \ \ \ \  trace_event_id_t\fP \fIevent\fP\fB, char *\fP\fIevent_name\fP\fB);
.br
\fP
.LP
\fBint posix_trace_trid_eventid_open(trace_id_t\fP \fItrid\fP\fB,
.br
\ \ \ \ \ \  const char *restrict\fP \fIevent_name\fP\fB,
.br
\ \ \ \ \ \  trace_event_id_t *restrict\fP \fIevent\fP\fB); \fP
\fB
.br
\fP
.SH DESCRIPTION
.LP
The \fIposix_trace_eventid_equal\fP() function shall compare the trace
event type identifiers \fIevent1\fP and \fIevent2\fP
from the same trace stream or the same trace log identified by the
\fItrid\fP argument. If the trace event type identifiers
\fIevent1\fP and \fIevent2\fP are from different trace streams, the
return value shall be unspecified.
.LP
The \fIposix_trace_eventid_get_name\fP() function shall return, in
the argument pointed to by \fIevent_name\fP, the trace
event name associated with the trace event type identifier identified
by the argument \fIevent\fP, for the trace stream or for the
trace log identified by the \fItrid\fP argument. The name of the trace
event shall have a maximum of {TRACE_EVENT_NAME_MAX}
characters (which has the minimum value {_POSIX_TRACE_EVENT_NAME_MAX}).
Successive calls to this function with the same trace event
type identifier and the same trace stream identifier shall return
the same event name.
.LP
The \fIposix_trace_trid_eventid_open\fP() function shall associate
a user trace event name with a trace event type identifier for
a given trace stream. The trace stream is identified by the \fItrid\fP
argument, and it shall be an active trace stream. The trace
event name is the string pointed to by the argument \fIevent_name\fP.
It shall have a maximum of {TRACE_EVENT_NAME_MAX} characters
(which has the minimum value {_POSIX_TRACE_EVENT_NAME_MAX}). The number
of user trace event type identifiers that can be defined
for any given process is limited by the maximum value {TRACE_USER_EVENT_MAX},
which has the minimum value
{_POSIX_TRACE_USER_EVENT_MAX}.
.LP
If the Trace Inherit option is not supported, the \fIposix_trace_trid_eventid_open\fP()
function shall associate the user trace
event name pointed to by the \fIevent_name\fP argument with a trace
event type identifier that is unique for the process being
traced in the trace stream identified by the \fItrid\fP argument,
and is returned in the variable pointed to by the \fIevent\fP
argument. If the user trace event name has already been mapped for
the traced process, then the previously assigned trace event
type identifier shall be returned. If the per-process user trace event
name limit represented by {TRACE_USER_EVENT_MAX} has been
reached, the pre-defined POSIX_TRACE_UNNAMED_USEREVENT (see \fITrace
Option: User Trace
Event\fP ) user trace event shall be returned. 
.LP
If the Trace Inherit option is supported, the \fIposix_trace_trid_eventid_open\fP()
function shall associate the user
trace event name pointed to by the \fIevent_name\fP argument with
a trace event type identifier that is unique for all the
processes being traced in the trace stream identified by the \fItrid\fP
argument, and is returned in the variable pointed to by
the \fIevent\fP argument. If the user trace event name has already
been mapped for the traced processes, then the previously
assigned trace event type identifier shall be returned. If the per-process
user trace event name limit represented by
{TRACE_USER_EVENT_MAX} has been reached, the pre-defined POSIX_TRACE_UNNAMED_USEREVENT
(see \fITrace Option: User Trace Event\fP ) user trace event shall
be returned. 
.SH RETURN VALUE
.LP
Upon successful completion, the \fIposix_trace_eventid_get_name\fP()
and  
\fIposix_trace_trid_eventid_open\fP()  functions shall return a
value of zero. Otherwise, they shall return the corresponding error
number.
.LP
The \fIposix_trace_eventid_equal\fP() function shall return a non-zero
value if \fIevent1\fP and \fIevent2\fP are equal;
otherwise, a value of zero shall be returned. No errors are defined.
If either \fIevent1\fP or \fIevent2\fP are not valid trace
event type identifiers for the trace stream specified by \fItrid\fP
or if the \fItrid\fP is invalid, the behavior shall be
unspecified.
.LP
The \fIposix_trace_eventid_get_name\fP() function stores the trace
event name value in the object pointed to by
\fIevent_name\fP, if successful.
.LP
The \fIposix_trace_trid_eventid_open\fP() function stores the trace
event type identifier value in the object pointed to by
\fIevent\fP, if successful. 
.SH ERRORS
.LP
The \fIposix_trace_eventid_get_name\fP() and   \fIposix_trace_trid_eventid_open\fP()
functions shall fail if:
.TP 7
.B EINVAL
The \fItrid\fP argument was not a valid trace stream identifier.
.sp
.LP
The \fIposix_trace_trid_eventid_open\fP() function shall fail if:
.TP 7
.B ENAMETOOLONG
.sp
The size of the name pointed to by the \fIevent_name\fP argument was
longer than the implementation-defined value
{TRACE_EVENT_NAME_MAX}. 
.sp
.LP
The \fIposix_trace_eventid_get_name\fP() function shall fail if:
.TP 7
.B EINVAL
The trace event type identifier \fIevent\fP was not associated with
any name.
.sp
.LP
\fIThe following sections are informative.\fP
.SH EXAMPLES
.LP
None.
.SH APPLICATION USAGE
.LP
None.
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
None.
.SH SEE ALSO
.LP
\fITrace Option: User Trace Event\fP , \fIposix_trace_event\fP() ,
\fIposix_trace_getnext_event\fP() , the Base Definitions volume of
IEEE\ Std\ 1003.1-2001, \fI<trace.h>\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 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 .