freebsd-skq/share/man/man9/DEVICE_PROBE.9

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.Dd June 16, 1998
.Os
.Dt DEVICE_PROBE 9
.Os FreeBSD
.Sh NAME
.Nm DEVICE_PROBE
.Nd probe for device existence
.Sh SYNOPSIS
.Fd #include <sys/param.h>
.Fd #include <sys/bus.h>
.Ft int
.Fn DEVICE_PROBE "device_t dev"
.Sh DESCRIPTION
.Pp
This device method should probe to see if the device is present. If
the device exists, the probe should return 0, otherwise ENXIO should
be returned. If some other error happens during the probe (such as a
memory allocation failure), an appropriate error code should be returned.
.Pp
Devices which implement busses should use this method to probe for the
existence of devices attached to the bus and add them as children. If
this is combined with the use of
.Xr bus_generic_attach 9
the child devices will be automatically probed and attached.
.Sh RETURN VALUES
Zero is returned on success, otherwise an error is returned.
.Sh SEE ALSO
.Xr device 9 ,
.Xr DEVICE_ATTACH 9
.Sh AUTHORS
This man page was written by
.An Doug Rabson .