illumos: manual page: project

PROJECT_WALK(3PROJECT) Project Database Access Library Functions

NAME

project_walk - visit active project IDs on current system

SYNOPSIS

cc [ flag ... ] file... -lproject [ library ... ]
#include <project.h>

int project_walk(int (*callback)(const projid_t project,
void *walk_data), void *init_data);

DESCRIPTION

The project_walk() function provides a mechanism for the application
author to examine all active projects on the current system. The
callback function provided by the application is given the ID of an
active project 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, project_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 project_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 projects available on the system.

The following example counts the number of projects available on the
system.

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

typedef struct wdata {
uint_t count;
} wdata_t;

wdata_t total_count;

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

...

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

ATTRIBUTES