
set_stream(+StreamId, +Stream)

   The symbolic stream name StreamId is associated with the stream Stream.



Arguments
   +StreamId           Atom.
   +Stream             Integer (stream number) or Atom (reserved or user-defined                symbolic stream name).

Type
   Stream I/O

Description
   Assigns the logical stream StreamId to the stream Stream.


   Logical streams may be matched to their physical stream numbers by using
   get_stream/2.


   Stream can be any existing stream number or symbolic stream name as long
   as it has a mode compatible with that of StreamId.


   StreamId can be a user-defined symbolic stream name, or else one of the
   system systems:  input , output , error, user, warning_output, log_output.


   A user-defined symbolic stream is not automatically updated when the
   stream to which it points is changed or closed.




Resatisfiable
      No.

Fail Conditions
      None.



Exceptions
     4 --- Either StreamId or Stream is uninstantiated.
     5 --- Either StreamId is not an atom or Stream is not a stream    number or symbolic stream name.
   193 --- Stream is an illegal stream specification.
   194 --- A physical stream has more than 255 logical stream names    assigned to it.

Examples
   
Success:
      [eclipse]: open(file1,update,s), set_stream(output,s),
      > writeln(output,hi), flush(output).
      yes.
      [eclipse]: seek(s,0), read(s,X).
      X = hi
      yes.
Error:
      set_stream(a, S).        (Error 4).
      set_stream(1.0, S).      (Error 5).
      set_stream(a, nonex).    (Error 193).





See Also
   open / 4, get_stream / 2
