f837c471db
devtoname(3) is a nonexistent function. We do have devtoname(9), but that's entirely different. The correct function is devname(3).
91 lines
2.8 KiB
Groff
91 lines
2.8 KiB
Groff
.\" Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd September 28, 2008
|
|
.Dt MAKEDEV 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm makedev ,
|
|
.Nm major ,
|
|
.Nm minor
|
|
.Nd device number conversion
|
|
.Sh SYNOPSIS
|
|
.In sys/types.h
|
|
.Ft dev_t
|
|
.Fn makedev "int major" "int minor"
|
|
.Ft int
|
|
.Fn major "dev_t dev"
|
|
.Ft int
|
|
.Fn minor "dev_t dev"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn makedev
|
|
macro allows a unique device number to be generated based on its
|
|
.Fa major
|
|
and
|
|
.Fa minor
|
|
number.
|
|
The
|
|
.Fn major
|
|
and
|
|
.Fn minor
|
|
macros can be used to obtain the original numbers from the device number
|
|
.Fa dev .
|
|
.Pp
|
|
In previous implementations of
|
|
.Fx
|
|
all block and character devices were uniquely identified by a pair of
|
|
major and minor numbers.
|
|
The major number referred to a certain device class (e.g. disks, TTYs)
|
|
while the minor number identified an instance within the device class.
|
|
Later versions of
|
|
.Fx
|
|
automatically generate a unique device number for each character device
|
|
visible in
|
|
.Pa /dev/ .
|
|
These numbers are not divided in device classes.
|
|
.Pp
|
|
On
|
|
.Fx
|
|
these macros are only used by utilities that need to exchange numbers
|
|
with other operating systems that may use different encodings for
|
|
.Vt dev_t ,
|
|
but also applications that present these numbers to the user in a more
|
|
conventional way.
|
|
.Sh RETURN VALUES
|
|
The
|
|
.Fn major
|
|
macro returns a device major number that has a value between 0 and 255.
|
|
The
|
|
.Fn minor
|
|
macro returns a device minor number whose value can span the complete
|
|
range of an
|
|
.Vt int .
|
|
.Sh SEE ALSO
|
|
.Xr devfs 5 ,
|
|
.Xr devname 3 ,
|
|
.Xr mknod 2
|