OPEN(II)                      8/5/73                     OPEN(II)

     open - open for reading or writing

     (open = 5.)
     sys open; name; mode
     (file descriptor in r0)

     open(name, mode)
     char *name;

     Open opens the file name for reading (if mode is 0), writing
     (if mode is 1) or for both reading and writing (if  mode  is
     2).   Name  is  the  address of a string of ASCII characters
     representing a path name, terminated by a null character.

     The returned file descriptor should be saved for  subsequent
     calls to read, write, and close.

     creat(II), read(II), write(II), close(II)

     The  error bit (c-bit) is set if the file does not exist, if
     one of the necessary directories does not exist  or  is  un-
     readable,  if  the file is not readable (resp. writable), or
     if too many files are open.  From C, a -1 value is  returned
     on an error.

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