[apple/libc.git] / gen / devname.3

.\" Copyright (c) 1993
.\"	The Regents of the University of California.  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.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
.\"
.\"     @(#)devname.3	8.2 (Berkeley) 4/29/95
.\" $FreeBSD: src/lib/libc/gen/devname.3,v 1.11 2001/10/01 16:08:50 ru Exp $
.\"
.Dd October 25, 2004
.Dt DEVNAME 3
.Os
.Sh NAME
.Nm devname ,
.Nm devname_r
.Nd get device name
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In sys/stat.h
.In stdlib.h
.Ft char *
.Fo devname
.Fa "dev_t dev"
.Fa "mode_t type"
.Fc
.Ft char *
.Fo devname_r
.Fa "dev_t dev"
.Fa "mode_t type"
.Fa "char *buf"
.Fa "int len"
.Fc
.Sh DESCRIPTION
The
.Fn devname
function returns a pointer to the name of the block or character
device in
.Dq Pa /dev
with a device number of
.Fa dev ,
and a file type matching the one encoded in
.Fa type
which must be one of
.Dv S_IFBLK
or
.Dv S_IFCHR .
If no device matches the specified values, or no information is
available, NULL is returned.
.Pp
The
.Fn devname
function uses a static buffer, which will be overwritten
on subsequent calls.
The
.Fn devname_r
functions takes a buffer and length as arguments to avoid this problem.
.Pp
The traditional display for applications when no device is
found is the string
.Dq ?? .
.Sh SEE ALSO
.Xr stat 2 ,
.Xr dev_mkdb 8
.Sh HISTORY
The
.Fn devname
function call appeared in
.Bx 4.4 .
Commit	Line	Data
5b2abdfb	1	.\" Copyright (c) 1993
e9ce8d39 A	2	.\" The Regents of the University of California. All rights reserved.
	3	.\"
	4	.\" Redistribution and use in source and binary forms, with or without
	5	.\" modification, are permitted provided that the following conditions
	6	.\" are met:
	7	.\" 1. Redistributions of source code must retain the above copyright
	8	.\" notice, this list of conditions and the following disclaimer.
	9	.\" 2. Redistributions in binary form must reproduce the above copyright
	10	.\" notice, this list of conditions and the following disclaimer in the
	11	.\" documentation and/or other materials provided with the distribution.
	12	.\" 3. All advertising materials mentioning features or use of this software
	13	.\" must display the following acknowledgement:
	14	.\" This product includes software developed by the University of
	15	.\" California, Berkeley and its contributors.
	16	.\" 4. Neither the name of the University nor the names of its contributors
	17	.\" may be used to endorse or promote products derived from this software
	18	.\" without specific prior written permission.
	19	.\"
	20	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	.\" SUCH DAMAGE.
	31	.\"
5b2abdfb A	32	.\" @(#)devname.3 8.2 (Berkeley) 4/29/95
5b2abdfb A	33	.\" $FreeBSD: src/lib/libc/gen/devname.3,v 1.11 2001/10/01 16:08:50 ru Exp $
e9ce8d39	34	.\"
3d9156a7	35	.Dd October 25, 2004
5b2abdfb	36	.Dt DEVNAME 3
e9ce8d39 A	37	.Os
e9ce8d39 A	38	.Sh NAME
224c7076 A	39	.Nm devname ,
224c7076 A	40	.Nm devname_r
5b2abdfb	41	.Nd get device name
e9ce8d39 A	42	.Sh LIBRARY
	43	.Lb libc
	44	.Sh SYNOPSIS
5b2abdfb A	45	.In sys/stat.h
	46	.In stdlib.h
	47	.Ft char *
224c7076 A	48	.Fo devname
	49	.Fa "dev_t dev"
	50	.Fa "mode_t type"
	51	.Fc
3d9156a7	52	.Ft char *
224c7076 A	53	.Fo devname_r
	54	.Fa "dev_t dev"
	55	.Fa "mode_t type"
	56	.Fa "char *buf"
	57	.Fa "int len"
	58	.Fc
e9ce8d39 A	59	.Sh DESCRIPTION
e9ce8d39 A	60	The
5b2abdfb A	61	.Fn devname
	62	function returns a pointer to the name of the block or character
	63	device in
	64	.Dq Pa /dev
	65	with a device number of
	66	.Fa dev ,
	67	and a file type matching the one encoded in
	68	.Fa type
3d9156a7 A	69	which must be one of
	70	.Dv S_IFBLK
	71	or
	72	.Dv S_IFCHR .
5b2abdfb A	73	If no device matches the specified values, or no information is
	74	available, NULL is returned.
	75	.Pp
3d9156a7 A	76	The
	77	.Fn devname
	78	function uses a static buffer, which will be overwritten
	79	on subsequent calls.
	80	The
	81	.Fn devname_r
	82	functions takes a buffer and length as arguments to avoid this problem.
	83	.Pp
5b2abdfb A	84	The traditional display for applications when no device is
	85	found is the string
	86	.Dq ?? .
e9ce8d39	87	.Sh SEE ALSO
5b2abdfb A	88	.Xr stat 2 ,
5b2abdfb A	89	.Xr dev_mkdb 8
e9ce8d39 A	90	.Sh HISTORY
e9ce8d39 A	91	The
5b2abdfb A	92	.Fn devname
5b2abdfb A	93	function call appeared in
e9ce8d39	94	.Bx 4.4 .