UMASK(2)            Linux Programmer's Manual            UMASK(2)

NAME
       umask - set file creation mask

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

       mode_t umask(mode_t 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 the mode argument to
       open(2) (so, for example, the common umask  default  value
       of 022 results in new files being created with permissions
       0666 & ~022 = 0644 = rw-r--r-- in the usual case where the
       mode is specified as 0666).

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)

Linux                     9 August 1998                         1