NetBSD/lib/libc/gen/devname.3
joerg 1907ec3a61 Switch device database to cdb(5). Rework ttyname(3) and ttyname_r(3) to
depend on new devname_r(3) as heart. Add /dev/pts magic directly to
devname(3). While it can lead to returning non-existing paths, the
behavior is more consistent that way. Drop caching layer in devname(3),
it doesn't buy anything for the common case of having access to the
database. Teach devname(3) proper fallback behavior of scanning /dev.
Create both old-style and new-style database for now in /etc/rc.d/sysdb.
2012-06-03 21:42:44 +00:00

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.\" $NetBSD: devname.3,v 1.12 2012/06/03 21:42:46 joerg Exp $
.\"
.\" Copyright (c) 1993
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.\" @(#)devname.3 8.2 (Berkeley) 4/29/95
.\"
.Dd June 3, 2012
.Dt DEVNAME 3
.Os
.Sh NAME
.Nm devname
.Nd get device name
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In stdlib.h
.In sys/stat.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.
If no device matches the specified values, or no information is
available,
.Dv 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.cdb -compact
.It Pa /var/run/dev.cdb
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 .