[Info-vax] openvms and xterm

[David Goodwin]

In article <v04epp$jd4t$1 at dont-email.me>, ldo at nz.invalid says...
> 
> On Sun, 21 Apr 2024 19:14:59 -0400, Arne Vajhøj wrote:
> 
> > On 4/21/2024 7:07 PM, Lawrence D'Oliveiro wrote:
> >>
> >> On Sun, 21 Apr 2024 11:20:03 +0200, Andreas Eder wrote:
> >>>
> >>> I think the problem is that they grew up in a Windows dominated world,
> >>> not like us greybeards.
> >> 
> >> If only Windows had Linux-style service management, don?t you think?
> >> Imagine being able to add/remove, enable/disable and start/stop
> >> individual services without having to reboot the entire system!
> > 
> > They don't need to imagine. They have been doing that for decades.

Indeed. If anything, Linux has acquired Windows NT style service 
management and logging with systemd. There is no general requirement to 
reboot for managing services. But some specific services can't always be 
safely restarted on a running system.

Things like device drivers, filesystem drivers, the win32 environment 
subsystem (of which csrss.exe is the usermode part), core system 
libraries.

Linux is no different here. Want to upgrade your X server? Going to have 
to at least restart all X11 apps. Want your update to Gtk or Qt to 
actually take effect? All software using those is going to have to be 
restarted. Rather than trying to figure out which software is or isn't 
affected by some library update its easer to just reboot the whole 
machine.

> Windows can?t even update a DLL that is in use by running processes. I
> suppose it inherited that file-locking mentality from VMS.
> 
> Look at the long list of reasons why Windows needs a reboot here, from
> Microsoft itself:
> <https://learn.microsoft.com/en-us/troubleshoot/windows-server/installing-updates-features-roles/why-prompted-restart-computer>.

Those reasons all look pretty reasonable to me. You'd usually have to 
reboot on Linux for most of those reasons too if you want the update to 
actually take effect. 

Remember that Windows NT doesn't have a monolithic kernel like Linux. 
Just because its a .exe or .dll doesn't mean its some trivial user-space 
thing that the system can continue running without.

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.

And some services are actually hardware device drivers, or filesystem 
drivers. Some drivers support being restarted online (graphics drivers 
usually), but others are not so safely restarted on a running system.