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+.\" 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"
+.Ft char *
+.Fn fdevname "int fd"
+.Ft char *
+.Fn fdevname_r "int fd" "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
+The
+.Fn fdevname
+and
+.Fn fdevname_r
+function obtains the device name directly from a file descriptor
+pointing to a character device.
+If it is unable to come up with a suitable name, these functions will
+return a NULL pointer.
+.Pp
+.Fn devname
+and
+.Fn fdevname
+return the name stored in a static buffer which will be overwritten
+on subsequent calls.
+.Fn devname_r
+and
+.Fn fdevname_r
+take 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));
+	printf("fdevname is /dev/%s\en", fdevname(fd));
+.Ed
+.Sh SEE ALSO
+.Xr stat 2
+.Sh HISTORY
+The
+.Fn devname
+function appeared in
+.Bx 4.4 .
+The
+.Fn fdevname
+function appeared in
+.Fx 8.0 .