[Simh] OpenBSD on Simh VAX 3.8-1 - Segmentation fault

[Mark Pizzolato]

Hi Gary,

On Tuesday, November 7, 2017 at 5:29 AM, Gary Lee Phillips wrote:
> I am running VAX 3.8-1 on a 64-bit Linux system. It performs well 
> with OpenVMS as the operating system. But when I try to run it 
> with OpenBSD 5.7 there are issues.
>
> The base system installs and boots correctly. But in order to bring
> in tools such as language compilers or editors, it is necessary to 
> use ftp or sftp. I cannot get these to transfer anything because the 
> moment a transfer starts, no matter which mode or direction or 
> whether the transfer is initiated from within OpenBSD or from the 
> outside, an immediate segmentation fault occurs. This appears to 
> be within the SimH code itself, and not on OpenBSD.

That would certainly seem to be the case.  Simulator crashes 
definitely should be fixed.  3.8-1 was released some 8 years ago, 
and 3.9 was some 6 years ago.  Both are way behind the current
code base located at https://github.com/simh/simh/ downloadable 
as https://github.com/simh/simh/archive/master.zip

> The same SimH VAX environment running OpenVMS 7.3 can 
> perform transfers over ethernet without any apparent issues. 

This is a useful data point.

> I have tried running SimH in supervisor mode or in user mode, 
> same results. Also same results whether the transfer is initiated 
> by root or by a normal user account.

I wouldn't expect you to be able to run the simulator as non-root
and have Ethernet functionality...

> The ethernet connection itself seems to be working. Telnet 
> connections function normally, and ftp or sftp will pass directory 
> information and accept commands, but file transfers fail.
>
> I guess I could try another version of OpenBSD. Upgrading SimH 
> is also possible but a bit more daunting since 3.8 is what is offered 
> as current on my Linux distro. (Linux Mint 18 "Sarah" 64 bit generic 
> 4.4.0-97)

It really isn't particularly daunting:

First, you'll need the following:

	$ sudo apt install libpcap-dev
Then:
	$ wget https://github.com/simh/simh/archive/master.zip
	$ unzip master.zip
	$ cd simh-master
	$ make vax
	$# Start the newly built simulator:
	$ BIN/vax


If you see any sort of segmentation fault, there is a problem that needs 
fixing, and I'll be glad to address it.   If you have a problem please create
an issue at https://github.com/simh/simh/issues

- Mark