bsd/man/man2/umask.2

   1 .\"     $NetBSD: umask.2,v 1.6 1995/02/27 12:39:06 cgd Exp $
   2 .\"
   3 .\" Copyright (c) 1980, 1991, 1993
   4 .\"     The Regents of the University of California.  All rights reserved.
   5 .\"
   6 .\" Redistribution and use in source and binary forms, with or without
   7 .\" modification, are permitted provided that the following conditions
   8 .\" are met:
   9 .\" 1. Redistributions of source code must retain the above copyright
  10 .\"    notice, this list of conditions and the following disclaimer.
  11 .\" 2. Redistributions in binary form must reproduce the above copyright
  12 .\"    notice, this list of conditions and the following disclaimer in the
  13 .\"    documentation and/or other materials provided with the distribution.
  14 .\" 3. All advertising materials mentioning features or use of this software
  15 .\"    must display the following acknowledgement:
  16 .\"     This product includes software developed by the University of
  17 .\"     California, Berkeley and its contributors.
  18 .\" 4. Neither the name of the University nor the names of its contributors
  19 .\"    may be used to endorse or promote products derived from this software
  20 .\"    without specific prior written permission.
  21 .\"
  22 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25 .\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32 .\" SUCH DAMAGE.
  33 .\"
  34 .\"     @(#)umask.2     8.1 (Berkeley) 6/4/93
  35 .\"
  36 .Dd June 4, 1993
  37 .Dt UMASK 2
  38 .Os BSD 4
  39 .Sh NAME
  40 .Nm umask
  41 .Nd set file creation mode mask
  42 .Sh SYNOPSIS
  43 .Fd #include <sys/stat.h>
  44 .Ft mode_t
  45 .Fo umask
  46 .Fa "mode_t cmask"
  47 .Fc
  48 .Sh DESCRIPTION
  49 The
  50 .Fn umask
  51 routine sets the process's file mode creation mask to
  52 .Fa cmask
  53 and returns the previous value of the mask.
  54 The 9 low-order access permission bits of
  55 .Fa cmask
  56 are used by system calls, including
  57 .Xr open 2 ,
  58 .Xr mkdir 2 ,
  59 .Xr mkfifo 2 ,
  60 and
  61 .Xr mknod 2
  62 to turn off corresponding bits
  63 requested in file mode.
  64 (See
  65 .Xr chmod 2 ) .
  66 This clearing allows each user to restrict the default access
  67 to his files.
  68 .Pp
  69 The default mask value is S_IWGRP | S_IWOTH (022, write access for the
  70 owner only).
  71 Child processes inherit the mask of the calling process.
  72 .Sh RETURN VALUES
  73 The previous value of the file mode mask is returned by the call.
  74 .Sh ERRORS
  75 The
  76 .Fn umask
  77 function is always successful.
  78 .Sh LEGACY SYNOPSIS
  79 .Fd #include <sys/types.h>
  80 .Fd #include <sys/stat.h>
  81 .Pp
  82 The include file
  83 .In sys/types.h
  84 is necessary.
  85 .Sh SEE ALSO
  86 .Xr chmod 2 ,
  87 .Xr mkdir 2 ,
  88 .Xr mkfifo 2 ,
  89 .Xr mknod 2 ,
  90 .Xr open 2 ,
  91 .Xr compat 5
  92 .Sh STANDARDS
  93 The
  94 .Fn umask
  95 function call is expected to
  96 conform to
  97 .St -p1003.1-88 .