xref: /dragonfly/lib/libc/gen/devname.3 (revision 19fe1c42)
1.\" Copyright (c) 1993
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.\"
32.\"     @(#)devname.3	8.2 (Berkeley) 4/29/95
33.\" $FreeBSD: src/lib/libc/gen/devname.3,v 1.7.2.7 2003/03/15 15:11:05 trhodes Exp $
34.\" $DragonFly: src/lib/libc/gen/devname.3,v 1.5 2007/05/17 08:19:00 swildner Exp $
35.\"
36.Dd July 18, 1999
37.Dt DEVNAME 3
38.Os
39.Sh NAME
40.Nm devname ,
41.Nm devname_r
42.Nd get device name
43.Sh LIBRARY
44.Lb libc
45.Sh SYNOPSIS
46.In sys/stat.h
47.In stdlib.h
48.Ft char *
49.Fn devname "dev_t dev" "mode_t type"
50.Ft char *
51.Fn devname_r "dev_t dev" "mode_t type" "char *buf" "size_t len"
52.Sh DESCRIPTION
53The
54.Fn devname
55function returns a pointer to the name of the block or character
56device in
57.Pa /dev
58with a device number of
59.Fa dev ,
60and a file type matching the one encoded in
61.Fa type
62which must be one of
63.Dv S_IFBLK
64or
65.Dv S_IFCHR .
66To find the right name,
67.Fn devname
68first searches the device database created by
69.Xr dev_mkdb 8 ;
70if that fails, it will format the information encapsulated in
71.Fa dev
72and
73.Fa type
74in a human-readable format.
75.Pp
76.Fn devname
77returns a pointer to an internal static object; thus, subsequent calls will
78modify the same buffer.
79.Fn devname_r
80avoids this problem by taking a buffer and buffer length as arguments.
81.Sh SEE ALSO
82.Xr stat 2 ,
83.Xr dev_mkdb 8
84.Sh HISTORY
85The
86.Fn devname
87function appeared in
88.Bx 4.4 .
89