[Info-vax] openvms and xterm

[David Goodwin]

In article <v0a5vu$25fmt$1 at dont-email.me>, ldo at nz.invalid says...
> 
> On Wed, 24 Apr 2024 17:04:36 +1200, David Goodwin wrote:
> 
> > If anything, Linux has acquired Windows NT style service 
> > management and logging with systemd.
> 
> Did you know that systemd uses text-based config files in .INI format? The 
> same format Microsoft invented for Windows back in the 1980s, then junked 
> in favour of that stinking cesspool known as the Registry?

I do, I've written them before. But thats just the configuration storage 
format - the actual service management capabilities at this point is 
pretty similar. Here Linux is picking up features that Windows NT (and 
commercial Unix) has had for decades.

> > Linux is no different here. Want to upgrade your X server? Going to have
> > to at least restart all X11 apps.
> 
> That?s just logging out of a GUI session and logging in again.
> 
> And remember, you can have multiple GUI sessions logged in at once.

Yes, but for most people (myself included), there isn't much difference 
between logging off and on again and a full reboot. Either way I've 
still got to open all my stuff again and having to re-open all my stuff 
is the entire problem with rebooting.

Multiple sessions isn't a help here either unless you've got some 
mechanism in place to move clients between X servers during the upgrade. 
I guess you could do the same on Windows (it supports multiple sessions 
too) but the benefits likely don't outweigh the costs of all the added 
complexity.

> > For example, the csrss.exe mentioned in the article is the user-space
> > chunk of the Win32 environment subsystem - the thing that allows Windows
> > NT to run regular windows software.
> 
> There?s nothing like that needed on Linux.

Linux still has a userspace API - the implementation of it is just all 
statically linked into the kernel. If you want to update the parts that 
make up its userspace API thats a kernel update and a reboot, just like 
on Windows.

The difference here is that Windows NT isn't limited to a single 
userspace API/personality, historically it provided three (Win32, OS/2 
and POSIX) in addition to its own Native API. These lived entirely in 
userspace rather than statically linked into the kernel with the first 
user-space process (the Session Manager Subsystem) responsible for 
starting them along with the Service Control Manager, the Local Security 
Authority Subsystem Service, Windows Logon and other bits.