xref: /freebsd/lib/libc/gen/devname.3 (revision f04938aa8ec450549860e700a68d93ff726e5cc6)

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.\"     @(#)devname.3	8.2 (Berkeley) 4/29/95
.\" $FreeBSD$
.\"
.Dd April 29, 1995
.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"
.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.
To find the right name,
.Fn devname
first searches the device database created by
.Xr dev_mkdb 8 ;
if that fails, it asks the kernel via the
.Va kern.devname
sysctl.
If it was still 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.
.Sh SEE ALSO
.Xr stat 2 ,
.Xr dev_mkdb 8
.Sh HISTORY
The
.Fn devname
function call appeared in
.Bx 4.4 .
.Sh BUGS
The
.Fn devname
function returns a poiner to an internal static object;
thus, subsequent calls will modify the same buffer.