UMASK(2)

NAME
       umask - set file creation mask

SYNOPSIS
       #include <<sys/stat.h>>

       int umask(int mask);

DESCRIPTION
       umask sets the umask to mask & 0777.

       The  umask  is used by open(2) to set initial file permis-
       sions on a newly-created file.  Specifically,  permissions
       in  the  umask  are turned off from 0666 (so, for example,
       the common umask default value of 022 results in new files
       being  created  with  permissions 0666 & ~022 = 0755 = rw-
       r--r--).

RETURN VALUE
       This system call always succeeds and the previous value of
       the mask is returned.

CONFORMING TO
       SVr4, SVID, POSIX, X/OPEN, BSD 4.3

SEE ALSO
       creat(2) open(2)