Проект OpenNet: MAN tnfctl_probe_apply (3) Библиотечные вызовы (FreeBSD и Linux)

Интерактивная система просмотра системных руководств (man-ов)

tnfctl_probe_apply (3)

>> tnfctl_probe_apply (3) ( Solaris man: Библиотечные вызовы )

NAME

tnfctl_probe_apply, tnfctl_probe_apply_ids - iterate over probes

SYNOPSIS

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

tnfctl_errcode_t tnfctl_probe_apply(tnfctl_handle_t *hndl,
    tnfctl_probe_op_t probe_op, void *clientdata);

tnfctl_errcode_t tnfctl_probe_apply_ids(tnfctl_handle_t *hndl,
    ulong_t probe_count, ulong_t *probe_ids,
    tnfctl_probe_op_t probe_op, void *clientdata);

DESCRIPTION

tnfctl_probe_apply() is used to iterate over the probes controlled by hndl. For every probe, the probe_op function is called:

typedef tnfctl_errcode_t (*tnfctl_probe_op_t)(
        tnfctl_handle_t *hndl,
        tnfctl_probe_t *probe_hndl,
        void *clientdata);

Several predefined functions are available for use as probe_op. These functions are described in tnfctl_probe_state_get(3TNF).

The clientdata supplied in tnfctl_probe_apply() is passed in as the last argument of probe_op. The probe_hndl in the probe operation function can be used to query or change the state of the probe. See tnfctl_probe_state_get(3TNF). The probe_op function should return TNFCTL_ERR_NONE upon success. It can also return an error code, which will cause tnfctl_probe_apply() to stop processing the rest of the probes and return with the same error code. Note that there are five (5) error codes reserved that the client can use for its own semantics. See ERRORS.

The lifetime of probe_hndl is the same as the lifetime of hndl. It is good until hndl is closed by tnfctl_close(3TNF). Do not confuse a probe_hndl with hndl. The probe_hndl refers to a particular probe, while hndl refers to a process or the kernel. If probe_hndl is used in another libtnfctl(3TNF) interface, and it references a probe in a library that has been dynamically closed (see dlclose(3C)), then the error code TNFCTL_ERR_INVALIDPROBE will be returned by that interface.

tnfctl_probe_apply_ids() is very similar to tnfctl_probe_apply(). The difference is that probe_op is called only for probes that match a probe id specified in the array of integers referenced by probe_ids. The number of probe ids in the array should be specified in probe_count. Use tnfctl_probe_state_get() to get the probe_id that corresponds to the probe_handl.

RETURN VALUES

tnfctl_probe_apply() and tnfctl_probe_apply_ids() return TNFCTL_ERR_NONE upon success.

ERRORS

The following errors apply to both tnfctl_probe_apply() and tnfctl_probe_apply_ids():

TNFCTL_ERR_INTERNAL

: An internal error occurred.

TNFCTL_ERR_USR1

: Error code reserved for user.

TNFCTL_ERR_USR2

: Error code reserved for user.

TNFCTL_ERR_USR3

: Error code reserved for user.

TNFCTL_ERR_USR4

: Error code reserved for user.

TNFCTL_ERR_USR5

: Error code reserved for user.

tnfctl_probe_apply() and tnfctl_probe_apply_ids() also return any error returned by the callback function probe_op.

The following errors apply only to tnfctl_probe_apply_ids():

TNFCTL_ERR_INVALIDPROBE

: The probe handle is no longer valid. For example, the probe is in a library that has been closed by dlclose(3C).

EXAMPLES

Example 1 Enabling Probes

To enable all probes:

tnfctl_probe_apply(hndl, tnfctl_probe_enable, NULL);

Example 2 Disabling Probes

To disable the probes that match a certain pattern in the probe attribute string:

/* To disable all probes that contain the string "vm" */
tnfctl_probe_apply(hndl, select_disable, "vm");
static tnfctl_errcode_t
select_disable(tnfctl_handle_t *hndl, tnfctl_probe_t *probe_hndl,
void *client_data)
{
    char *pattern = client_data;
    tnfctl_probe_state_t probe_state;
    tnfctl_probe_state_get(hndl, probe_hndl, &probe_state);
    if (strstr(probe_state.attr_string, pattern)) {
         tnfctl_probe_disable(hndl, probe_hndl, NULL);
    }
}

Note that these examples do not have any error handling code.