The user-stream hook is, if defined, called during
SP_initialize(). It has the following prototype:
SP_stream *user_stream_hook(void *user_data, int which)
If the hook is not defined, then SICStus will attempt to open the standard TTY/console versions of these streams. If they are unavailable (such as for non-console executables under Windows), then the result is undefined.
It is called once for each stream. The
argument indicates which stream it is called for. The value
which is one of the following:
Create stream for standard input.
Create stream for standard output.
Create stream for standard error.
The set of possible values for
which may be expanded in
The hook should return a standard SICStus I/O stream, as described in Defining a New Stream.
See cpg-ref-SP_set_user_stream_hook for details.