Conference bulova::decw_jan-89_to_nov-90

     <<< Note 2451.0 by QUARK::LIONEL "Free advice is worth every cent" >>>
                    -< Getting SHOW DISPLAY info from DCL >-

>How can I, from DCL, get the information that SHOW DISPLAY tells me, without
>redirecting its output to a file?  In particular, I'd like the "Node"
>information.


$ SHOW DISPLAY/SYMBOL

$ sho symbol/glo/all

  DECW$DISPLAY_NODE == "VANITY"
  DECW$DISPLAY_SCREEN == "0"
  DECW$DISPLAY_SERVER == "0"
  DECW$DISPLAY_TRANSPORT == "DECNET"

Wonderful!  I wonder why this isn't documented (at least in HELP)?

I'll QAR that.

			Steve

Subject to change, maybe??

I doubt it will be changed.  I suspect that Jake VanNoy's thinking was that
there should be a more elegant method of performing the function, so he placed
it in the `obsolete unpublished features manual' immediately on implementation.

The development of SET/SHOW DISPLAY was done as a part of the DECwindows
stream, which we tried to keep as independent of the VMS master pack as
possible.  The SET/SHOW .CLD files had to change for SET/SHOW DISPLAY, but
the wall we had to scale to get F$DISPLAY() or some such thing seemed a bit
more than it was worth.  Using LIB$CREATE_SYMBOL (or whatever it is called)
was about 5 minutes work.

It did seem a little underdone, however, and that's why I never pushed to
have it documented.

Why couldn't there be logical names defined in the job table of the session
manager process, when it gets created?  One would have to think about what
mode they should be defined in (I'd presume exec).

			Steve

        Right.

	The real lack seems to be that there is no way to determine your 
	workstation node from your process, in order to do the 
	SET DISPLAY/CREATE that you MUST do, except manually. 

	When I SET HOST, SYS$REM_NODE and SYS$REM_ID in the process point back
	to the origin node. There's no equivalent for CREATE/TERM to utilize.

	It would be nice if some sort of equivalent logicals were in place.

	Kevin

    Along a similiar vein (not worth a topic)  How do I perform a set
    displ/node=blah/trans=foo from an image ?  So that the next image I
    invoke will use it ?  (I have priv's!)  Lib$do_command is out. (and
    spawn)
    
    I thought I could just $crelnm the decw$display logical to be blah::0.0
    or something, but this doesn't seem to work.
    
    Do I have to assign a channel to wsa0: and do some acpcontrol functions
    ? and then define decw$display to be that ?  Is this doc'ed anywhere ?
    
    Many thanks
    /Boy ( a bantam weight decw'er )

Essentially what you have to do is a SYS$ASSIGN to WSA0 (which clones you a new
WSA number).  Then do set_mode qios to it to set the values the way you want
them.  I don't know if it is documented anywhere.

You should be able to pass "mumble::0.0" as an argument to XOpenDisplay without
having to do the crelnm as well.

Burns

    
    I guess this belong's here-
    
    My customer needs to be able to do the reverse, that is GET the node,
    transport, display, and screen information in their running program.
    
    I'm guessing that it is a sense mode qio to the wsa device that
    DECW$DISPLAY points at, but I haven't been able to track down the
    various bits and pieces...
    
    If someone can point me in the right direction I'd really appreciate it.
    
    Alternately, if someone has some stripped code that would do it, that
    would be ideal.
    
    	Jan
    	dtn 533-7787

status = sys$qiow (0, chan, IO$_SENSEMODE|IO$M_WS_DISPLAY, &iosb, 0, 0,
                   itemval.dsc$a_pointer,
                   itemval.dsc$w_length,
                   item, 0, 0, 0);

Where itemval is a structure of dsc$descriptor (I.e. a string descriptor) and
item is one of:

DECW$C_WS_DSP_NODE
DECW$C_WS_DSP_TRANSPORT
DECW$C_WS_DSP_SERVER,
DECW$C_WS_DSP_SCREEN,

#define DECW$C_WS_DSP_NODE 1
#define DECW$C_WS_DSP_TRANSPORT 2
#define DECW$C_WS_DSP_SERVER 3
#define DECW$C_WS_DSP_SCREEN 4

    
    Thanks Burns-	(& Vince)
    
    Only one question: what is the value of IO$M_WS_DISPLAY ?
    
    I checked in iodef.h & iodef.mar, but there doesn't seem to be a value
    for the symbol. Did I miss something?
    
    
    	Jan 
    	dtn 533-7787

#define IO$M_WS_DISPLAY 64
 

RE: .8


setting display to BLAH::0.0 won't work very well.  BLAH is a MicroVAX
Config 5 and doesn't ahve any DECwindows displays connected to it.


-bill