PS: I have tried to open a terminal with another error:
$ show display
Device: WSA16: [super]
Node: 192.168.10.103
Transport: TCPIP
Server: 1
Screen: 0
$ create/term/detach
%DECW-E-CANT_OPEN_DISPL, Can't open display
I'm trying to configure XDMCP on OpenVMS 7.3/VAX (running on simh)
and I'm unable to obtain a running configuration.
X server is Xephyr running on hilbert (192.168.10.103). In a first
time, I have configured xdmcp on a foreign NetBSD server
(legendre, 192.168.10.128).
On 2025-05-23, JKB <JKB@hilbert.invalid> wrote:
PS: I have tried to open a terminal with another error:
$ show display
Device: WSA16: [super]
Node: 192.168.10.103
Transport: TCPIP
Server: 1
Screen: 0
$ create/term/detach
%DECW-E-CANT_OPEN_DISPL, Can't open display
Do you have to do something with xhost to allow access ?
It's been a _long_ time (I've run X over SSH for many years), but
IIRC, you had to use xhost on the target device to authorise incoming connections.
JKB <JKB@hilbert.invalid> writes:
I'm trying to configure XDMCP on OpenVMS 7.3/VAX (running on simh)
and I'm unable to obtain a running configuration.
X server is Xephyr running on hilbert (192.168.10.103). In a first
time, I have configured xdmcp on a foreign NetBSD server
(legendre, 192.168.10.128).
Which TCP stack are you using? The Compaq one that comes with 7.3 is so
old that only older things like PathWorks v7.4 under Windows or the Microvax2000 booted as a VXT off an Infoserver can catch the
display. Something must have changed between then and now. The Multinet
one you can catch with modern setups. At least this has been my finding
after wrestling with it.
Under X11, I could use either Xephyr or Xnest. Now under Wayland only
Xnest "works", with some issues (windows don't move/resize properly). I
have no experience with BSD to VMS: only Linux, Windows, and Solaris.
Xephyr :1 -ac -listen tcp -screen 1200x800 -from atr2.lan -retro -query kirin.lan
Xnest :1 -ac -listen tcp -from atr2.lan -retro -query kirin.lan
"-ac" turns off access control; you don't have to use xhost.
$ show display
Device: WSA2: [user]
Node: 192.168.20.1
Transport: TCPIP
Server: 1
Screen: 0
$ spawn /nowait mcr sys$system:decw$clock
This is with Slackware Linux Current/Wayland. In other words, you may
have to play around with it to get it working. If you want to use the microvax2000 off the infoserver100 (SIMH), here's the config for it
(assuming you have a bridge and the infoserver100 on it with VXT
installed). The software for the infoserver100/150 is in the file infoserver.zip that you see floating around online. Then you'll really
be retro with a monochrome VXT.
; MicroVAX 2000 (KA410)
; This is set up as a diskless Virtual X Terminal
; to be booted off an Infoserver that serves VXT.
; Max memory this model will support is 16M.
set cpu 16M
set cpu idle
set cpu conhalt
; Enable monocrome graphics display, "VC". "VA" is
; for color GPX, but will not boot off the infoserver
; (hangs).
;set va capture
;set va enable
;set cpu model=VAXstationGPX
set vc capture
set vc ena
; Non-volitile memory file goes here
att nvr nvr.bin
; Keep a log for debugging purposes
;set console log=console.log
; Disable disk drives since this is set up as
; a virtual X terminal thin client
set rd0 dis
set rd1 dis
set rd2 dis
; MAC address is set on NAR, this would be 1.16.
; Enable Lance ethernet controller and attach to tuntap
set nar mac=AA:00:04:00:10:04
set xs ena
att xs tap:tap7
; Start simulator
boot cpu
; Commands to boot VXT off the Infoserver:
; >>> b/101
; Bootfile: vxtldr
; VXTLDR> VXT.SYS
;
; Patience - it can take a while to load!
; Terminal group "XTERMINALS" password: VXT
; Manager password for group configuration: VXT
;
; EOF
That one will work for Compaq XDM, but not Multinet XDM. Xnest/Xephyr
work for Multinet, but not Compaq. Pathworks does both. YMMV.
X Toolkit Error: Can't Open display
%DWT-F-NOMSG, Message number 03AB8204
...
I don't understand why VMS answers "can't open display"...
On Sun, 25 May 2025 08:27:10 -0000 (UTC), JKB wrote:
X Toolkit Error: Can't Open display
%DWT-F-NOMSG, Message number 03AB8204
...
I don't understand why VMS answers "can't open display"...
Presumably that error code will give you a clue, you just don’t have a message section loaded that will show the corresponding message.
$ product show product tcpipThat looks like the Compaq one.
PRODUCT KIT TYPE STATE
DEC VAXVMS TCPIP V5.3-18 Full LP Installed ----------------------------------- ----------- ------------
I have tried with Xnest with the same result:You shouldn't have to set the display. That's the job of XDM. You only
$ set display/create/node=192.168.10.103/transport=tcpip/server=1
$ show display
Device: WSA17: [super]
Node: 192.168.10.103
Transport: TCPIP
Server: 1
Screen: 0
I will try xdm /after/ I'm able to display clock on Xnest/Xephyr. II guess I'm confused then, because your subject mentioned xdmcp. I
don't understand why VMS answers "can't open display"...
On 5/25/2025 5:44 AM, Lawrence D'Oliveiro wrote:
Presumably that error code will give you a clue, you just don’t have a
message section loaded that will show the corresponding message.
Unfortunately:
$ exit %x03ab8204
%DWT-F-NOMSG, Message number 03AB8204
$ set mes sys$message:decw$dwtmsg
$ exit %x03ab8204
%DWT-F-DWTABORT, xtoolkit fatal error
JKB <JKB@hilbert.invalid> writes:
$ product show product tcpipThat looks like the Compaq one.
PRODUCT KIT TYPE STATE
DEC VAXVMS TCPIP V5.3-18 Full LP Installed
----------------------------------- ----------- ------------
I have tried with Xnest with the same result:You shouldn't have to set the display. That's the job of XDM. You only
$ set display/create/node=192.168.10.103/transport=tcpip/server=1
$ show display
Device: WSA17: [super]
Node: 192.168.10.103
Transport: TCPIP
Server: 1
Screen: 0
have to do that if you rlogin/telnet or similar.
I will try xdm /after/ I'm able to display clock on Xnest/Xephyr. II guess I'm confused then, because your subject mentioned xdmcp. I
don't understand why VMS answers "can't open display"...
though you were using XDM.
If you are doing it "by hand", then just start Xnest/Xephyr with "-ac"
to turn off access control. From the VMS side, you can execute something
like this:
$ type xephyr.com
$! Command procedure to send X11 traffic to a Xephyr
$! nested XServer, by setting the DISPLAY.
$ SET DISPLAY/CREATE/TRANSPORT=TCPIP/NODE=192.168.20.1/SERVER=1/PERMANENT
$ DEFINE/SYSTEM DECW$DISPLAY 'F$TRNLNM("DECW$DISPLAY")
$ RUN SYS$SYSTEM:DECW$STARTLOGIN.EXE
$
SERVER corresponds with what Unix calls the :1.0 part of DISPLAY
(matching the above example). Chances are you main desktop is :0.0, so Xnest/Xephr would then be :1.0.
If you enable XDM, you don't have to run the above each time, and you'll
get a log file to check if something doesn't go right.
TCPIP> show service xdm /full
Service: XDM
State: Enabled
Port: 177 Protocol: UDP Address: 0.0.0.0 Inactivity: 0 User_name: TCPIP$XDM Process: TCPIP$XDM Limit: 1 Active: 0 Peak: 0
File: TCPIP$SYSTEM:TCPIP$XDM_RUN.COM
Flags: None
Socket Opts: Rcheck Scheck
Receive: 0 Send: 0
Log Opts: Acpt Actv Dactv Conn Error Exit Logi Logo Mdfy Rjct TimO Addr
File: SYS$SPECIFIC:[TCPIP$XDM]TCPIP$XDM_RUN.LOG
Security
Reject msg: not defined
Accept host: 0.0.0.0
Accept netw: 0.0.0.0
TCPIP> exit
$ type SYS$SPECIFIC:[TCPIP$XDM]TCPIP$XDM_RUN.LOG
$ Set NoOn
$ VERIFY = F$VERIFY(F$TRNLNM("SYLOGIN_VERIFY"))
12-MAY-2025 14:49:57.83 - Waiting for DECwindows to start...
12-MAY-2025 14:50:02.83 - Waiting for DECwindows to start...
12-MAY-2025 14:50:07.83 - Waiting for DECwindows to start... %SYSTEM-S-NORMAL, normal successful completion
%SYSTEM-S-NORMAL, normal successful completion
%SYSTEM-S-NORMAL, normal successful completion
%SYSTEM-S-NORMAL, normal successful completion
%SYSTEM-S-NORMAL, normal successful completion
%SYSTEM-S-NORMAL, normal successful completion
$
On Linux side, I use :
$ Xephyr -ac :1 -screen 1024x768 -listen tcp -query 192.168.10.107
On VMS side:
$ set display/create/node=192.168.10.103/transport=tcpip/server=1
$ DEFINE/SYSTEM DECW$DISPLAY 'F$TRNLNM("DECW$DISPLAY")
$ RUN SYS$SYSTEM:DECW$STARTLOGIN.EXE
$
No error, but startlogin doesn't appear on Xephyr.
$ mcr sys$system:decw$clock
X Toolkit Error: Can't Open display
%DWT-F-NOMSG, Message number 03AB8204
JKB <JKB@hilbert.invalid> writes:
On Linux side, I use :
$ Xephyr -ac :1 -screen 1024x768 -listen tcp -query 192.168.10.107
On VMS side:
$ set display/create/node=192.168.10.103/transport=tcpip/server=1
$ DEFINE/SYSTEM DECW$DISPLAY 'F$TRNLNM("DECW$DISPLAY")
$ RUN SYS$SYSTEM:DECW$STARTLOGIN.EXE
$
No error, but startlogin doesn't appear on Xephyr.
$ mcr sys$system:decw$clock
X Toolkit Error: Can't Open display
%DWT-F-NOMSG, Message number 03AB8204
If you want to do it "by hand" as above, leave off everything from
"-query" onward, including IP address. If you want to use XDM, use the
-query flag with IP and don't run any procedure on the VMS side. You're mixing two different things: you're telling Xephyr to contact an X
Display Manager at 192.168.10.107 and then trying to manually start
another session on top of 192.168.10.103:1.0
On 2025-05-27, JKB <JKB@hilbert.invalid> wrote:
$ mcr sys$system:decw$clock
X Toolkit Error: Can't Open display
%DWT-F-NOMSG, Message number 03AB8204
$
I don't understand difference between BSD export DISPLAY && xterm
and VMS set/display followed by mcr. There is no firewall on LAN.
This is now a job for Wireshark.
$ mcr sys$system:decw$clock
X Toolkit Error: Can't Open display
%DWT-F-NOMSG, Message number 03AB8204
$
I don't understand difference between BSD export DISPLAY && xterm
and VMS set/display followed by mcr. There is no firewall on LAN.
I don't understand difference between BSD export DISPLAY && xtermThere's not one. Those are the correct commands. From 192.168.20.1 to 192.168.20.3. I left the xkeyboard and font errors in for completeness.
and VMS set/display followed by mcr. There is no firewall on LAN.
Warning: Could not resolve keysym XF86RefreshRateToggleErrors from xkbcomp are not fatal to the X server
Warning: Could not resolve keysym XF86Accessibility
Warning: Could not resolve keysym XF86DoNotDisturb
I don't have wireshark but I have tried to check traffic with
tcpdump.
JKB <JKB@hilbert.invalid> writes:
I don't understand difference between BSD export DISPLAY && xtermThere's not one. Those are the correct commands. From 192.168.20.1 to 192.168.20.3. I left the xkeyboard and font errors in for completeness.
and VMS set/display followed by mcr. There is no firewall on LAN.
≻ Xephyr :1 -ac -listen tcp -screen 1024x768 -from atr2.lan &
≻ The XKEYBOARD keymap compiler (xkbcomp) reports:
Warning: Could not resolve keysym XF86RefreshRateToggleErrors from xkbcomp are not fatal to the X server
Warning: Could not resolve keysym XF86Accessibility
Warning: Could not resolve keysym XF86DoNotDisturb
r rlogin lunast
[TNDRIVER: Proxy login for user "jayjwa" in progress ...]
$ set display /create /node=192.168.20.1 /transport=tcpip /server=1
$ show display
Device: WSA19: [super]
Node: 192.168.20.1
Transport: TCPIP
Server: 1
Screen: 0
$ mcr decw$clock
X Toolkit Warning: Cannot convert string "-*-Menu-Medium-R-Normal--*-120-*-*-P-*-ISO8859-1" to type FontStruct
X Toolkit Warning: Cannot convert string "-*-Menu-Medium-R-Normal--*-120-*-*-P-*-ISO8859-1" to type FontStruct
X Toolkit Warning: Cannot convert string "-*-Menu-Medium-R-Normal--*-120-*-*-P-*-ISO8859-1" to type FontStruct
X Toolkit Warning: Cannot convert string "-*-Menu-Medium-R-Normal--*-120-*-*-P-*-ISO8859-1" to type FontStruct
(decwclock shows). You may have to consider your install/software kit is faulty if you are otherwise able to make TCP connections to/from the node.
$ @DECW$VERSIONS.COM
DECwindows ident is DW T1.2-6010221
DECwindows server ident is DW V7.1-010215
DECwindows transport ident is DW V7.3-010215
DECwindows xlib ident is DW T1.2-6010221
DECwindows OSF/Motif Toolkit ident is DW T1.2-6010221
DECwindows apps ident is DW V1.2-6010221
DECwindows programming ident is DW T1.2-6010221
not yours : DW V7.3-010215DECwindows xlib ident is DW T1.2-6010221
$ product show product tcpip
----------------------------------- ----------- ------------
PRODUCT KIT TYPE STATE ----------------------------------- ----------- ------------
DEC VAXVMS TCPIP V5.1-15 Full LP Installed ----------------------------------- ----------- ------------
1 item found
| Sysop: | Keyop |
|---|---|
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