UMASK(C)                             UNIX System V



     Name
          umask - sets file-creation mode mask


     Syntax
          umask [ 000 ]


     Description
          The user file-creation mode mask is set to 000.   The  three
          octal  digits  refer  to  read/write/execute permissions for
          owner, group, and others, respectively.  Only the  low-order
          9  bits  of  cmask and the file mode creation mask are used.
          The value of each specified digit is ``subtracted'' from the
          corresponding  ``digit''  specified  by  the  system for the
          creation of any file (see umask(S) or  creat(S)).   This  is
          actually  a  binary  masking  operation,  and  thus the name
          ``umask''.   In  general,  binary  ones   remove   a   given
          permission,  and  zeros have no effect at all.  For example,
          umask 022 removes group and others write  permission  (files
          normally  created  with  mode  777  become  mode 755 ; files
          created with mode 666 become mode 644).

          If 000 is omitted, the current value of the mask is printed.

          umask is recognized and executed by the shell.  By  default,
          login shells have a umask of 022.

          umask is built in to csh and sh.


     See Also
          chmod(C), csh(C), sh(C), chmod(S), creat(S), umask(S)


     Standards Conformance
          umask is conformant with:
          AT&T SVID Issue 2, Select Code 307-127;
          and The X/Open Portability Guide II of January 1987.


     (printed 2/15/90)                                   UMASK(C)