netbsd man page for umask

UMASK(2)						      BSD System Calls Manual							  UMASK(2)

NAME
     umask -- set file creation mode mask

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <sys/stat.h>

     mode_t
     umask(mode_t numask);

DESCRIPTION
     The umask() routine sets the process's file mode creation mask to numask and returns the previous value of the mask.  The 9 low-order access
     permission bits of numask are used by system calls, including open(2), mkdir(2), mkfifo(2) and mknod(2) to turn off corresponding bits
     requested in file mode.  (See chmod(2)).  This clearing allows each user to restrict the default access to his files.

     The default mask value is S_IWGRP|S_IWOTH (022, write access for the owner only).	Child processes inherit the mask of the calling process.

RETURN VALUES
     The previous value of the file mode mask is returned by the call.

ERRORS
     The umask() function is always successful.

SEE ALSO
     chmod(2), mkdir(2), mkfifo(2), mknod(2), open(2)

STANDARDS
     The umask() function conforms to ISO/IEC 9945-1:1990 (``POSIX.1'').

BSD
								   June 4, 1993 							       BSD