[Info-vax] Change Mouse Pointer Color

[Stephen Hoffman]

On 2018-12-03 16:38:47 +0000, Jairo Alves said:

> ... I thought the X protocol was used only to open a screen remotely 
> via the network. Do regular applications also run as X apps? I ask that 
> because in our case all the Scada apps are used directly on the OpenVMS 
> server, and not as  from a Linux or Windows thin-client, for example, 
> via the X11 protocol.

X is a remote procedure call implementation masquerading as a network- 
and remote-capable graphical user interface.

X Window client apps can run locally and can connect locally to an X 
Window Server on a local display, or can run locally and connect to a X 
Window server on a remote client.  The X client is the app and its use 
of X libraries and frameworks, and the X server is the hunk of X code 
that managing the X display.

You're going to have to be slightly more specific about what you mean 
by a "regular app" here, as regular apps apps such as LSEDIT, NOTES, 
the Debugger, and other pieces and parts can all provide local and 
remote graphical user interfaces via X.  And those same apps can also 
display via character cell, though that character cell display might 
itself be viewed across a DECterm (which is an X client) showing the 
character cell terminal session remotely on an X server.  You're also 
going to want to describe what the app display and display software and 
display hardware might involve in a little more detail, too.

Command-line apps don't usually display a cursor themselves, leaving 
that detail to the terminal or terminal emulator.

In addition to X, there have been a few graphics interfaces and other 
tooling found on OpenVMS—VWS/UIS and ReGIS among those—that can provide 
their own cursors.  That's all really old, though.  There are also 
forms-management packages including FMS, TDMS and DECforms, and 
there've been occasional other packages around.

For an intro to X on OpenVMS:

https://www.cs.auckland.ac.nz/references/unix/digital/AQ917BTE/DOCU_001.HTM
https://www.itec.suny.edu/scsys/vms/OVMSDOC073/v73/5633/5633PRO.HTML
https://en.wikipedia.org/wiki/X_Window_System#Client–server_separation
etc.

> Looking forward, for VSI, such an option would be welcome, 
> particularlly in the Industrial Automation world, since most screens 
> these days are dark.
...
> Most operating screens are designed to be "low distraction" when 
> nothing special is happening, so I guess that's why.

VSI has not particularly discussed OpenVMS updates for DECwindows and 
X, and has specifically discussed that they're not targeting 
workstations.

I'd expect that most new GUIs are HTTPS-based using HTML and 
JavaScript, or more recently using JavaScript and WebAssembly more 
directly, or servers configured to communicate using REST or ilk in 
conjunction with a local client app running on the target client 
device.  I'd expect these apps to be sending alerts and notifications 
via push notifications or similar means.  This all not likely using X 
and not using command-line displays and terminals and 
terminal-emulation character-cell displays, save for those existing 
environments where that's already been in use and where there's not 
been a push for migration.  Yeah, SCADA installs have been around for a 
very long time, and which means there are numerous existing installs 
that won't get upgraded until they get replaced, too.



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