TNFCTL_TRACE_STATE_SET(3TNF) TNF Library Functions TNFCTL_TRACE_STATE_SET(3TNF)


NAME


tnfctl_trace_state_set, tnfctl_filter_state_set, tnfctl_filter_list_get,
tnfctl_filter_list_add, tnfctl_filter_list_delete - control kernel
tracing and process filtering

SYNOPSIS


cc [ flag ... ] file ... -ltnfctl [ library ... ]
#include <tnf/tnfctl.h>

tnfctl_errcode_t tnfctl_trace_state_set(tnfctl_handle_t *hndl,
boolean_t trace_state);


tnfctl_errcode_t tnfctl_filter_state_set(tnfctl_handle_t *hndl,
boolean_t filter_state);


tnfctl_errcode_t tnfctl_filter_list_get(tnfctl_handle_t *hndl,
pid_t **pid_list, int *pid_count);


tnfctl_errcode_t tnfctl_filter_list_add(tnfctl_handle_t *hndl,
pid_t pid_to_add);


tnfctl_errcode_t tnfctl_filter_list_delete(tnfctl_handle_t *hndl,
pid_t pid_to_delete);


DESCRIPTION


The interfaces to control kernel tracing and process filtering are used
only with kernel handles, handles created by tnfctl_kernel_open(3TNF).
These interfaces are used to change the tracing and filter states for
kernel tracing.


tnfctl_trace_state_set() sets the kernel global tracing state to "on" if
trace_state is B_TRUE, or to "off" if trace_state is B_FALSE. For the
kernel, trace_state is off by default.Probes that are enabled will not
write out data unless this state is on. Use tnfctl_trace_attrs_get(3TNF)
to retrieve the current tracing state.


tnfctl_filter_state_set() sets the kernel process filtering state to "on"
if filter_state is B_TRUE, or to "off" if filter_state is B_FALSE.
filter_state is off by default. If it is on, only probe points
encountered by processes in the process filter set by
tnfctl_filter_list_add() will generate trace points. Use
tnfctl_trace_attrs_get(3TNF) to retrieve the current process filtering
state.


tnfctl_filter_list_get() returns the process filter list as an array in
pid_list. The count of elements in the process filter list is returned in
pid_count. The caller should use free(3C) to free memory allocated for
the array pid_list.


tnfctl_filter_list_add() adds pid_to_add to the process filter list.
The process filter list is maintained even when the process filtering
state is off, but it has no effect unless the process filtering state is
on.


tnfctl_filter_list_delete() deletes pid_to_delete from the process filter
list. It returns an error if the process does not exist or is not in
the filter list.

RETURN VALUES


The interfaces tnfctl_trace_state_set(), tnfctl_filter_state_set(),
tnfctl_filter_list_add(), tnfctl_filter_list_delete(), and
tnfctl_filter_list_get() return TNFCTL_ERR_NONE upon success.

ERRORS


The following error codes apply to tnfctl_trace_state_set:

TNFCTL_ERR_BADARG
The handle is not a kernel handle.


TNFCTL_ERR_NOBUF
Cannot turn on tracing without a buffer being
allocated.


TNFCTL_ERR_BUFBROKEN
Tracing is broken in the target.


TNFCTL_ERR_INTERNAL
An internal error occurred.


The following error codes apply to tnfctl_filter_state_set:

TNFCTL_ERR_BADARG
The handle is not a kernel handle.


TNFCTL_ERR_INTERNAL
An internal error occurred.


The following error codes apply to tnfctl_filter_list_add:

TNFCTL_ERR_BADARG
The handle is not a kernel handle.


TNFCTL_ERR_NOPROCESS
No such process exists.


TNFCTL_ERR_ALLOCFAIL
A memory allocation failure occurred.


TNFCTL_ERR_INTERNAL
An internal error occurred.


The following error codes apply to tnfctl_filter_list_delete:

TNFCTL_ERR_BADARG
The handle is not a kernel handle.


TNFCTL_ERR_NOPROCESS
No such process exists.


TNFCTL_ERR_INTERNAL
An internal error occurred.


The following error codes apply to tnfctl_filter_list_get:

TNFCTL_ERR_BADARG
The handle is not a kernel handle.


TNFCTL_ERR_ALLOCFAIL
A memory allocation failure occurred.


TNFCTL_ERR_INTERNAL
An internal error occurred.


ATTRIBUTES


See attributes(5) for descriptions of the following attributes:


+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|MT Level | MT-Safe |
+---------------+-----------------+

SEE ALSO


prex(1), TNF_PROBE(3TNF), free(3C), libtnfctl(3TNF),
tnfctl_kernel_open(3TNF), tnfctl_trace_attrs_get(3TNF), tracing(3TNF),
tnf_kernel_probes(4), attributes(5)


March 4, 1997 TNFCTL_TRACE_STATE_SET(3TNF)