1.\" $NetBSD: devname.3,v 1.8 2002/02/07 07:00:11 ross Exp $ 2.\" 3.\" Copyright (c) 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)devname.3 8.2 (Berkeley) 4/29/95 35.\" 36.Dd April 29, 1995 37.Dt DEVNAME 3 38.Os 39.Sh NAME 40.Nm devname 41.Nd get device name 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.Fd #include \*[Lt]stdlib.h\*[Gt] 46.Fd #include \*[Lt]sys/stat.h\*[Gt] 47.Ft char * 48.Fn devname "dev_t dev" "mode_t type" 49.Sh DESCRIPTION 50The 51.Fn devname 52function returns a pointer to the name of the block or character 53device in 54.Dq Pa /dev 55with a device number of 56.Fa dev , 57and a file type matching the one encoded in 58.Fa type 59which must be one of S_IFBLK or S_IFCHR. 60The device name is cached so that multiple calls with the same 61.Fa dev 62and 63.Fa type 64do not require additional queries of the device database file. 65If no device matches the specified values, or no information is 66available, NULL is returned. 67.Pp 68The traditional display for applications when no device is 69found is the string 70.Dq ?? . 71.Sh FILES 72.Bl -tag -width /var/run/dev.db -compact 73.It Pa /var/run/dev.db 74Device database file. 75.El 76.Sh SEE ALSO 77.Xr stat 2 , 78.Xr dev_mkdb 8 79.Sh HISTORY 80The 81.Nm devname 82function call appeared in 83.Bx 4.4 . 84