xref: /csrg-svn/lib/libc/sys/umask.2 (revision 61186)
1*61186Sbostic.\" Copyright (c) 1980, 1991, 1993
2*61186Sbostic.\"	The Regents of the University of California.  All rights reserved.
320050Smckusick.\"
447208Scael.\" %sccs.include.redist.man%
520050Smckusick.\"
6*61186Sbostic.\"     @(#)umask.2	8.1 (Berkeley) 06/04/93
747208Scael.\"
847208Scael.Dd
947208Scael.Dt UMASK 2
1047208Scael.Os BSD 4
1147208Scael.Sh NAME
1247208Scael.Nm umask
1347208Scael.Nd set file creation mode mask
1447208Scael.Sh SYNOPSIS
1547208Scael.Fd #include <sys/stat.h>
1647208Scael.Ft mode_t
1747208Scael.Fn umask "mode_t numask"
1847208Scael.Sh DESCRIPTION
1947208ScaelThe
2047208Scael.Fn umask
2147208Scaelroutine sets the process's file mode creation mask to
2247208Scael.Fa numask
2347208Scaeland returns the previous value of the mask.  The 9 low-order
2447208Scaelaccess permission
2547208Scaelbits of
2647208Scael.Fa numask
2747208Scaelare used by system calls, including
2847208Scael.Xr open 2 ,
2947208Scael.Xr mkdir 2 ,
3047208Scaeland
3147208Scael.Xr mkfifo 2 ,
3247208Scaelto turn off corresponding bits
3347208Scaelrequested in file mode.
3453132Sbostic(See
3547208Scael.Xr chmod 2 ) .
3620051SmckusickThis clearing allows each user to restrict the default access
3720051Smckusickto his files.
3847208Scael.Pp
3953132SbosticThe default mask value is S_IWGRP|S_IWOTH (022, write access for the
4053132Sbosticowner only).
4147208ScaelChild processes inherit the mask of the calling process.
4247208Scael.Sh RETURN VALUES
4320051SmckusickThe previous value of the file mode mask is returned by the call.
4447208Scael.Sh ERRORS
4547208ScaelThe
4647208Scael.Fn umask
4747208Scaelfunction is always successful.
4847208Scael.Sh SEE ALSO
4947208Scael.Xr chmod 2 ,
5047208Scael.Xr mknod 2 ,
5147208Scael.Xr open 2
5247208Scael.Sh STANDARDS
5347208ScaelThe
5447208Scael.Fn umask
5553132Sbosticfunction call is expected to conform to IEEE Std 1003.1-1988
5647208Scael.Pq Dq Tn POSIX .
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