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.\" 4. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)devname.3 8.2 (Berkeley) 4/29/95 29.\" $FreeBSD$ 30.\" 31.Dd February 22, 2005 32.Dt DEVNAME 3 33.Os 34.Sh NAME 35.Nm devname 36.Nd "get device name" 37.Sh LIBRARY 38.Lb libc 39.Sh SYNOPSIS 40.In sys/stat.h 41.In stdlib.h 42.Ft char * 43.Fn devname "dev_t dev" "mode_t type" 44.Ft char * 45.Fn devname_r "dev_t dev" "mode_t type" "char *buf" "int len" 46.Sh DESCRIPTION 47The 48.Fn devname 49function returns a pointer to the name of the block or character 50device in 51.Pa /dev 52with a device number of 53.Fa dev , 54and a file type matching the one encoded in 55.Fa type 56which must be one of 57.Dv S_IFBLK 58or 59.Dv S_IFCHR . 60To find the right name, 61.Fn devname 62asks the kernel via the 63.Va kern.devname 64sysctl. 65If it is unable to come up with a suitable name, 66it will format the information encapsulated in 67.Fa dev 68and 69.Fa type 70in a human-readable format. 71.Pp 72.Fn devname 73returns the name stored in a static buffer which will be overwritten 74on subsequent calls. 75.Fn devname_r 76takes a buffer and length as argument to avoid this problem. 77.Sh EXAMPLES 78.Bd -literal -compact 79int fd; 80struct stat buf; 81char *name; 82 83 fd = open("/dev/tun"); 84 fstat(fd, &buf); 85 printf("devname is /dev/%s\en", devname(buf.st_rdev, S_IFCHR)); 86.Ed 87.Sh SEE ALSO 88.Xr stat 2 89.Sh HISTORY 90The 91.Fn devname 92function appeared in 93.Bx 4.4 . 94