device_has_children(9)

device_has_children9

Examine devices connected to a device

Part of device_get_children(9).

Usage

#include <sys/param.h>

#include <sys/bus.h>

int

device_get_children(device_t dev, device_t **devlistp, int *devcountp);

bool

device_has_children(device_t dev);

Overview

The device_get_children function retrieves a list of all device instances currently connected to dev. It returns the list in *devlistp and the count in *devcountp. The memory allocated for the list should be freed using free(*devlistp, M_TEMP). devlistp and devcountp are not changed when an error is returned.

As a special case, if devlistp is null, no memory is allocated but the count is still returned in *devcountp.

The device_has_children function returns true if dev has at least one child and false if it has none.

Return values

The device_get_children function returns zero on success and an appropriate error otherwise. The device_has_children function returns true if the specified device has at least one child and false otherwise.

Releases

Unchanged in 4 releases since FreeBSD 14.4-RELEASE.

  1. 14.4–16.0

Authors

This manual page was written by Doug Rabson ⟨[email protected]⟩ and Dag-Erling Smørgrav ⟨[email protected]⟩.

From base 16.0-CURRENT-20261027-61c70dc16a79 in FreeBSD 16.0-CURRENT (2026-10-27). Parsed by carta from the page's mdoc source.