получить атрибуты трассировки или статус трассировки (TRACING) (retrieve the trace attributes or trace status (TRACING))
Пролог (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.
Имя (Name)
posix_trace_get_attr, posix_trace_get_status — retrieve the trace
attributes or trace status (TRACING)
Синопсис (Synopsis)
#include <trace.h>
int posix_trace_get_attr(trace_id_t trid, trace_attr_t *attr);
int posix_trace_get_status(trace_id_t trid,
struct posix_trace_status_info *statusinfo);
Описание (Description)
The posix_trace_get_attr() function shall copy the attributes of
the active trace stream identified by trid into the object
pointed to by the attr argument. If the Trace Log option is
supported, trid may represent a pre-recorded trace log.
The posix_trace_get_status() function shall return, in the
structure pointed to by the statusinfo argument, the current
trace status for the trace stream identified by the trid
argument. These status values returned in the structure pointed
to by statusinfo shall have been appropriately read to ensure
that the returned values are consistent. If the Trace Log option
is supported and the trid argument refers to a pre-recorded trace
stream, the status shall be the status of the completed trace
stream.
Each time the posix_trace_get_status() function is used, the
overrun status of the trace stream shall be reset to
POSIX_TRACE_NO_OVERRUN immediately after the call completes. If
the Trace Log option is supported, the posix_trace_get_status()
function shall behave the same as when the option is not
supported except for the following differences:
* If the trid argument refers to a trace stream with log, each
time the posix_trace_get_status() function is used, the log
overrun status of the trace stream shall be reset to
POSIX_TRACE_NO_OVERRUN and the flush_error status shall be
reset to zero immediately after the call completes.
* If the trid argument refers to a pre-recorded trace stream,
the status returned shall be the status of the completed
trace stream and the status values of the trace stream shall
not be reset.
Возвращаемое значение (Return value)
Upon successful completion, these functions shall return a value
of zero. Otherwise, they shall return the corresponding error
number.
The posix_trace_get_attr() function stores the trace attributes
in the object pointed to by attr, if successful.
The posix_trace_get_status() function stores the trace status in
the object pointed to by statusinfo, if successful.
Ошибки (Error)
These functions shall fail if:
EINVAL The trace stream argument trid does not correspond to a
valid active trace stream or a valid trace log.
The following sections are informative.
Примеры (Examples)
None.
Использование в приложениях (Application usage)
None.
Обоснование (Rationale)
None.
Будущие направления (Future directions)
The posix_trace_get_attr() and posix_trace_get_status() functions
may be removed in a future version.
Смотри также (See also)
posix_trace_attr_destroy(3p), posix_trace_close(3p),
posix_trace_create(3p)
The Base Definitions volume of POSIX.1‐2017, trace.h(0p)
