5 ms·

X11 is a network protocol. The process which created this X11 windows could be on a different box, running in the kernel or have the whole X11 exchange replayed

X11 is a network protocol. The process which created this X11 windows could be on a different box, running in the kernel or have the whole X11 exchange replayed from the magnetic tape.

nwatson 3y ago
The posed question addresses this in the second paragraph, after the very short first paragraph.
jameshart 3y ago
Presumably which of these states of affairs pertains to a specific window is, though, at some level knowable. The question of which process created the window is not necessarily bounded to ‘processes running in user space on this machine right now’, but something created it. And 99% of the time the answer will be a locally running process, which makes it a highly pertinent question even without the caveats. It’s not clever to point out that a question may not have a simple answer and therefore to reject the question as flawed.
- arethuza 3y ago
  "And 99% of the time the answer will be a locally running process" Depends on the environment - for years I used either an HP X terminal or a PC running an X server and the one thing I could be confident about in both cases was that the process wasn't running locally. Mind you - that wasn't recently!
- cduzz 3y ago
  From a 2020's perspective, X11 is deeply weird. It was written back when huge enormous servers were the only systems with enough oomph to do anything useful, and those servers had 128mb of ram (think of something like a sun 3/480 with a 33mhz 68030). It was common to have a room of X terminals each with 1-8mb of ram for a 15-19 inch display (with 1-8bit color). In that context, everything ran on another system, often you'd have processes running on several different systems and you'd have to be careful about managing authorization otherwise people would figure out your DISPLAY and run their programs against your X terminal (innocuous, like 300 Xeyes programs or malicious like a keyboard snooper, depending on where and when). In 2020 this whole scenario sounds absurd, but it was the way of things from when X11 was designed and through the first 15 years of X being a thing. In some ways, the question is like asking "what is the process ID that generated this http response?" [edited to add the analogy]
  - toast0 3y ago
    > From a 2020's perspective, X11 is deeply weird. X11 is a distributed systems non-meshed networking protocol, that outputs to screens as a side effect. Knowing about Erlang dist and figuring out how to do X11 a few years ago, everything makes a lot of sense. Except for xlib. xlib is a bit better now, but it turns a pretty decent (but certainly not without flaws) async protocol and implements blocking synchronous calls... And then most toolkits were based on that. Sometimes you really do need to wait for a reply, but so many things don't need it, and all the waiting makes actually networked X much less usable.:(
  - PaulDavisThe1st 3y ago
    > In 2020 this whole scenario sounds absurd It's not really absurd at all. In fact, the increase in processor speed, core count and installed RAM means that it even more likely that in a given context, a single desktop computer system has far more capacity than a single user needs. So, you extend the number of users that can utilize that capacity by sitting them in front of an X Terminal, which from their perspective is just like sitting in front of the "real" monitor of the machine. This doesn't make sense for gamers, compile-happy developers or data crunching, but then this model never made sense for those use cases. But a dentist's office with a central desktop and 8 users? You just don't need 8 computers - 1 computer plus 7 or 8 X Terminals is far better use of resources.
    - cduzz 3y ago
      A random piece of junk refurbished dell small computer from amazon with a windows 10 pro license is $200. It's more powerful than every single computer I administered from 1990-2005, put together. What you say is true -- they don't really need the power, but golly they've got it anyhow.
  - hulitu 3y ago
    > In 2020 this whole scenario sounds absurd Why ? I use Citrix at work in 2023 and nobody thinks it absurd to run the program on another computer and display it on yours. Except the wayland developers (last i heard). /s

X11 is a network protocol. The process which created this X11 windows could be on a different box, running in the kernel or have the whole X11 exchange replayed from the magnetic tape.

nwatson 3y ago

The posed question addresses this in the second paragraph, after the very short first paragraph.

jameshart 3y ago

Presumably which of these states of affairs pertains to a specific window is, though, at some level knowable. The question of which process created the window is not necessarily bounded to ‘processes running in user space on this machine right now’, but something created it. And 99% of the time the answer will be a locally running process, which makes it a highly pertinent question even without the caveats. It’s not clever to point out that a question may not have a simple answer and therefore to reject the question as flawed.

arethuza 3y ago
"And 99% of the time the answer will be a locally running process" Depends on the environment - for years I used either an HP X terminal or a PC running an X server and the one thing I could be confident about in both cases was that the process wasn't running locally. Mind you - that wasn't recently!
cduzz 3y ago
From a 2020's perspective, X11 is deeply weird. It was written back when huge enormous servers were the only systems with enough oomph to do anything useful, and those servers had 128mb of ram (think of something like a sun 3/480 with a 33mhz 68030). It was common to have a room of X terminals each with 1-8mb of ram for a 15-19 inch display (with 1-8bit color). In that context, everything ran on another system, often you'd have processes running on several different systems and you'd have to be careful about managing authorization otherwise people would figure out your DISPLAY and run their programs against your X terminal (innocuous, like 300 Xeyes programs or malicious like a keyboard snooper, depending on where and when). In 2020 this whole scenario sounds absurd, but it was the way of things from when X11 was designed and through the first 15 years of X being a thing. In some ways, the question is like asking "what is the process ID that generated this http response?" [edited to add the analogy]
- toast0 3y ago
  > From a 2020's perspective, X11 is deeply weird. X11 is a distributed systems non-meshed networking protocol, that outputs to screens as a side effect. Knowing about Erlang dist and figuring out how to do X11 a few years ago, everything makes a lot of sense. Except for xlib. xlib is a bit better now, but it turns a pretty decent (but certainly not without flaws) async protocol and implements blocking synchronous calls... And then most toolkits were based on that. Sometimes you really do need to wait for a reply, but so many things don't need it, and all the waiting makes actually networked X much less usable.:(
- PaulDavisThe1st 3y ago
  > In 2020 this whole scenario sounds absurd It's not really absurd at all. In fact, the increase in processor speed, core count and installed RAM means that it even more likely that in a given context, a single desktop computer system has far more capacity than a single user needs. So, you extend the number of users that can utilize that capacity by sitting them in front of an X Terminal, which from their perspective is just like sitting in front of the "real" monitor of the machine. This doesn't make sense for gamers, compile-happy developers or data crunching, but then this model never made sense for those use cases. But a dentist's office with a central desktop and 8 users? You just don't need 8 computers - 1 computer plus 7 or 8 X Terminals is far better use of resources.
  - cduzz 3y ago
    A random piece of junk refurbished dell small computer from amazon with a windows 10 pro license is $200. It's more powerful than every single computer I administered from 1990-2005, put together. What you say is true -- they don't really need the power, but golly they've got it anyhow.
- hulitu 3y ago
  > In 2020 this whole scenario sounds absurd Why ? I use Citrix at work in 2023 and nobody thinks it absurd to run the program on another computer and display it on yours. Except the wayland developers (last i heard). /s