RCTL_WALK(3C) Standard C Library Functions RCTL_WALK(3C)

NAME

rctl_walk - visit registered rctls on current system

SYNOPSIS

#include <rctl.h>

int rctl_walk(int (*callback)(const char *rctlname, void *walk_data),
void *init_data);

DESCRIPTION

The rctl_walk() function provides a mechanism for the application
author to examine all active resource controls (rctls) on the current
system. The callback function provided by the application is given
the name of an rctl at each invocation and can use the walk_data to
record its own state. The callback function should return non-zero if
it encounters an error condition or attempts to terminate the walk
prematurely; otherwise the callback function should return 0.

RETURN VALUES

Upon successful completion, rctl_walk() returns 0. It returns -1 if
the callback function returned a non-zero value or if the walk
encountered an error, in which case errno is set to indicate the
error.

ERRORS

The rctl_walk() function will fail if:

ENOMEM
There is insufficient memory available to set up the
initial data for the walk.


Other returned error values are presumably caused by the callback
function.

EXAMPLES

Example 1: Count the number of rctls available on the system.

The following example counts the number of resource controls on the
system.


#include <sys/types.h>
#include <rctl.h>
#include <stdio.h>

typedef struct wdata {
uint_t count;
} wdata_t;

wdata_t total_count;

int
simple_callback(const char *name, void *pvt)
{
wdata_t *w = (wdata_t *)pvt;
w->count++;
return (0);
}

...

total_count.count = 0;
errno = 0;
if (rctl_walk(simple_callback, &total_count)) == 0)
(void) printf("count = %u\n", total_count.count);

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Evolving |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+

SEE ALSO

setrctl(2), attributes(7)

January 1, 2001 RCTL_WALK(3C)