NetBSD/lib/libc/gen/devname.3

.\"	$NetBSD: devname.3,v 1.8 2002/02/07 07:00:11 ross Exp $
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.\"     @(#)devname.3	8.2 (Berkeley) 4/29/95
.\"
.Dd April 29, 1995
.Dt DEVNAME 3
.Os
.Sh NAME
.Nm devname
.Nd get device name
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.Fd #include \*[Lt]stdlib.h\*[Gt]
.Fd #include \*[Lt]sys/stat.h\*[Gt]
.Ft char *
.Fn devname "dev_t dev" "mode_t type"
.Sh DESCRIPTION
The
.Fn devname
function returns a pointer to the name of the block or character
device in
.Dq 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 S_IFBLK or S_IFCHR.
The device name is cached so that multiple calls with the same
.Fa dev
and
.Fa type
do not require additional queries of the device database file.
If no device matches the specified values, or no information is
available, NULL is returned.
.Pp
The traditional display for applications when no device is
found is the string
.Dq ?? .
.Sh FILES
.Bl -tag -width /var/run/dev.db -compact
.It Pa /var/run/dev.db
Device database file.
.El
.Sh SEE ALSO
.Xr stat 2 ,
.Xr dev_mkdb 8
.Sh HISTORY
The
.Nm devname
function call appeared in
.Bx 4.4 .