xref: /freebsd/lib/libc/gen/devname.3 (revision 529ac58781315d051c9cd091fb023da1ad40eb01)
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32.\"     @(#)devname.3	8.2 (Berkeley) 4/29/95
33.\" $FreeBSD$
34.\"
35.Dd July 18, 1999
36.Dt DEVNAME 3
37.Os
38.Sh NAME
39.Nm devname
40.Nd get device name
41.Sh LIBRARY
42.Lb libc
43.Sh SYNOPSIS
44.In sys/stat.h
45.In stdlib.h
46.Ft char *
47.Fn devname "dev_t dev" "mode_t type"
48.Ft char *
49.Fn devname_r "dev_t dev" "mode_t type" "char *buf" "int len"
50.Sh DESCRIPTION
51The
52.Fn devname
53function returns a pointer to the name of the block or character
54device in
55.Pa /dev
56with a device number of
57.Fa dev ,
58and a file type matching the one encoded in
59.Fa type
60which must be one of
61.Dv S_IFBLK
62or
63.Dv S_IFCHR .
64To find the right name,
65.Fn devname
66asks the kernel via the
67.Va kern.devname
68sysctl.
69If it is unable to come up with a suitable name,
70it will format the information encapsulated in
71.Fa dev
72and
73.Fa type
74in a human-readable format.
75.Pp
76.Fn devname
77returns the name stored in a static buffer which will be overwritten
78on subsequent calls.
79.Fn devname_r
80takes a buffer and length as argument to avoid this problem.
81.Sh SEE ALSO
82.Xr stat 2 ,
83.Sh HISTORY
84The
85.Fn devname
86function appeared in
87.Bx 4.4 .
88