posix_trace_attr_getlogsize(3p) — Linux manual page

PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

POSIX_T...TLOGSIZE(3P)  POSIX Programmer's Manual  POSIX_T...TLOGSIZE(3P)

PROLOG         top

       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         top

       posix_trace_attr_getlogsize, posix_trace_attr_getmaxdatasize,
       posix_trace_attr_getmaxsystemeventsize,
       posix_trace_attr_getmaxusereventsize,
       posix_trace_attr_getstreamsize, posix_trace_attr_setlogsize,
       posix_trace_attr_setmaxdatasize, posix_trace_attr_setstreamsize —
       retrieve and set trace stream size attributes (TRACING)

SYNOPSIS         top

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

       int posix_trace_attr_getlogsize(const trace_attr_t *restrict attr,
           size_t *restrict logsize);
       int posix_trace_attr_getmaxdatasize(const trace_attr_t *restrict attr,
           size_t *restrict maxdatasize);
       int posix_trace_attr_getmaxsystemeventsize(
           const trace_attr_t *restrict attr,
           size_t *restrict eventsize);
       int posix_trace_attr_getmaxusereventsize(
           const trace_attr_t *restrict attr,
           size_t data_len, size_t *restrict eventsize);
       int posix_trace_attr_getstreamsize(const trace_attr_t *restrict attr,
           size_t *restrict streamsize);
       int posix_trace_attr_setlogsize(trace_attr_t *attr,
           size_t logsize);
       int posix_trace_attr_setmaxdatasize(trace_attr_t *attr,
           size_t maxdatasize);
       int posix_trace_attr_setstreamsize(trace_attr_t *attr,
           size_t streamsize);

DESCRIPTION         top

       The  posix_trace_attr_getlogsize()  function  shall  copy  the log
       size, in bytes, from the log-max-size attribute of the  attributes
       object  pointed  to by the attr argument into the variable pointed
       to by the logsize argument. This log size is the maximum total  of
       bytes  that shall be allocated for system and user trace events in
       the trace log. The default value for the log-max-size attribute is
       implementation-defined.

       The posix_trace_attr_setlogsize() function shall set  the  maximum
       allowed  size,  in  bytes,  in  the  log-max-size attribute of the
       attributes object pointed to by the attr argument, using the  size
       value supplied by the logsize argument.

       The  trace log size shall be used if the log-full-policy attribute
       is set to POSIX_TRACE_LOOP or POSIX_TRACE_UNTIL_FULL. If the  log-
       full-policy   attribute   is   set   to   POSIX_TRACE_APPEND,  the
       implementation shall ignore the log-max-size attribute.

       The  posix_trace_attr_getmaxdatasize()  function  shall  copy  the
       maximum  user  trace event data size, in bytes, from the max-data-
       size attribute of the attributes object pointed  to  by  the  attr
       argument into the variable pointed to by the maxdatasize argument.
       The   default   value   for   the   max-data-size   attribute   is
       implementation-defined.

       The   posix_trace_attr_getmaxsystemeventsize()   function    shall
       calculate  the  maximum memory size, in bytes, required to store a
       single system trace event. This value is calculated for the  trace
       stream  attributes  object  pointed to by the attr argument and is
       returned in the variable pointed to by the eventsize argument.

       The values returned as the maximum memory sizes of  the  user  and
       system  trace  events shall be such that if the sum of the maximum
       memory sizes of a set of the trace events that may be recorded  in
       a  trace  stream  is  less  than  or  equal to the stream-min-size
       attribute of that trace stream, the system provides the  necessary
       resources for recording all those trace events, without loss.

       The    posix_trace_attr_getmaxusereventsize()    function    shall
       calculate the maximum memory size, in bytes, required to  store  a
       single user trace event generated by a call to posix_trace_event()
       with a data_len parameter equal to the data_len value specified in
       this   call.  This  value  is  calculated  for  the  trace  stream
       attributes object pointed to by the attr argument and is  returned
       in the variable pointed to by the eventsize argument.

       The   posix_trace_attr_getstreamsize()  function  shall  copy  the
       stream size, in bytes, from the stream-min-size attribute  of  the
       attributes  object  pointed  to  by  the  attr  argument  into the
       variable pointed to by the streamsize argument.

       This stream size is the current total  memory  size  reserved  for
       system  and  user  trace  events  in the trace stream. The default
       value for the stream-min-size attribute is implementation-defined.
       The stream size  refers  to  memory  used  to  store  trace  event
       records.  Other  stream data (for example, trace attribute values)
       shall not be included in this size.

       The  posix_trace_attr_setmaxdatasize()  function  shall  set   the
       maximum  allowed size, in bytes, in the max-data-size attribute of
       the attributes object pointed to by the attr argument,  using  the
       size value supplied by the maxdatasize argument. This maximum size
       is  the  maximum allowed size for the user data argument which may
       be passed to posix_trace_event().   The  implementation  shall  be
       allowed  to  truncate  data  passed  to  trace_user_event which is
       longer than maxdatasize.

       The  posix_trace_attr_setstreamsize()  function  shall   set   the
       minimum  allowed  size, in bytes, in the stream-min-size attribute
       of the attributes object pointed to by the  attr  argument,  using
       the size value supplied by the streamsize argument.

RETURN VALUE         top

       Upon  successful  completion, these functions shall return a value
       of zero. Otherwise, they  shall  return  the  corresponding  error
       number.

       The  posix_trace_attr_getlogsize()  function  stores  the  maximum
       trace log allowed size in the object pointed  to  by  logsize,  if
       successful.

       The  posix_trace_attr_getmaxdatasize() function stores the maximum
       trace event record  memory  size  in  the  object  pointed  to  by
       maxdatasize, if successful.

       The  posix_trace_attr_getmaxsystemeventsize()  function stores the
       maximum memory size to store a single system trace  event  in  the
       object pointed to by eventsize, if successful.

       The  posix_trace_attr_getmaxusereventsize()  function  stores  the
       maximum memory size to store a single  user  trace  event  in  the
       object pointed to by eventsize, if successful.

       The  posix_trace_attr_getstreamsize()  function stores the maximum
       trace stream allowed size in the object pointed to by  streamsize,
       if successful.

ERRORS         top

       These functions may fail if:

       EINVAL The value specified by one of the arguments is invalid.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       None.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       The following functions:

              posix_trace_attr_getlogsize()
              posix_trace_attr_getmaxdatasize()
              posix_trace_attr_getmaxsystemeventsize()
              posix_trace_attr_getmaxusereventsize()
              posix_trace_attr_getstreamsize()
              posix_trace_attr_setlogsize()
              posix_trace_attr_setmaxdatasize()
              posix_trace_attr_setstreamsize()

       may be removed in a future version.

SEE ALSO         top

       posix_trace_attr_destroy(3p), posix_trace_create(3p),
       posix_trace_event(3p), posix_trace_get_attr(3p)

       The  Base  Definitions  volume  of  POSIX.1‐2017, sys_types.h(0p),
       trace.h(0p)

COPYRIGHT         top

       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 .

IEEE/The Open Group                2017            POSIX_T...TLOGSIZE(3P)

Pages that refer to this page: trace.h(0p)posix_trace_attr_getstreamsize(3p)posix_trace_attr_setlogsize(3p)posix_trace_attr_setstreamsize(3p)