gen/devname.3

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  32 .\"     @(#)devname.3   8.2 (Berkeley) 4/29/95
  33 .\" $FreeBSD: src/lib/libc/gen/devname.3,v 1.11 2001/10/01 16:08:50 ru Exp $
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  35 .Dd October 25, 2004
  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
  51 The
  52 .Fn devname
  53 function returns a pointer to the name of the block or character
  54 device in
  55 .Dq Pa /dev
  56 with a device number of
  57 .Fa dev ,
  58 and a file type matching the one encoded in
  59 .Fa type
  60 which must be one of
  61 .Dv S_IFBLK
  62 or
  63 .Dv S_IFCHR .
  64 If no device matches the specified values, or no information is
  65 available, NULL is returned.
  66 .Pp
  67 The
  68 .Fn devname
  69 function uses a static buffer, which will be overwritten
  70 on subsequent calls.
  71 The
  72 .Fn devname_r
  73 functions takes a buffer and length as arguments to avoid this problem.
  74 .Pp
  75 The traditional display for applications when no device is
  76 found is the string
  77 .Dq ?? .
  78 .Sh SEE ALSO
  79 .Xr stat 2 ,
  80 .Xr dev_mkdb 8
  81 .Sh HISTORY
  82 The
  83 .Fn devname
  84 function call appeared in
  85 .Bx 4.4 .