94 lines
2.8 KiB
Groff
94 lines
2.8 KiB
Groff
.\" 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.
|
|
.\" 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
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd February 22, 2005
|
|
.Dt DEVNAME 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm devname
|
|
.Nd "get device name"
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In sys/stat.h
|
|
.In stdlib.h
|
|
.Ft char *
|
|
.Fn devname "dev_t dev" "mode_t type"
|
|
.Ft char *
|
|
.Fn devname_r "dev_t dev" "mode_t type" "char *buf" "int len"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn devname
|
|
function returns a pointer to the name of the block or character
|
|
device in
|
|
.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 .
|
|
To find the right name,
|
|
.Fn devname
|
|
asks the kernel via the
|
|
.Va kern.devname
|
|
sysctl.
|
|
If it is unable to come up with a suitable name,
|
|
it will format the information encapsulated in
|
|
.Fa dev
|
|
and
|
|
.Fa type
|
|
in a human-readable format.
|
|
.Pp
|
|
.Fn devname
|
|
returns the name stored in a static buffer which will be overwritten
|
|
on subsequent calls.
|
|
.Fn devname_r
|
|
takes a buffer and length as argument to avoid this problem.
|
|
.Sh EXAMPLES
|
|
.Bd -literal -compact
|
|
int fd;
|
|
struct stat buf;
|
|
char *name;
|
|
|
|
fd = open("/dev/tun");
|
|
fstat(fd, &buf);
|
|
printf("devname is /dev/%s\en", devname(buf.st_rdev, S_IFCHR));
|
|
.Ed
|
|
.Sh SEE ALSO
|
|
.Xr stat 2
|
|
.Sh HISTORY
|
|
The
|
|
.Fn devname
|
|
function appeared in
|
|
.Bx 4.4 .
|