[Simh] Telnet problem with WinXP

[Mark Emmer]

Hello all,

I’m running the SDS 940 simulator on WinXP SP3. When I go to attach the SDS
communications mux, I get this:

SDS 940 simulator V4.0-0 Beta        git commit id: $Format:
sim> attach mux 23
Sockets: bind error 10048 - Address already in use
File open error
sim>

By building the simulator with Visual C++ 2010 Express, I tried to
breakpoint and debug the socket logic.  But every time I did, the attach
would work properly.  I began to suspect a timing issue, and indeed, adding
Sleep(1); as the first statement in sim_master_sock() in sim_sock.c fixes
the problem.  Sleep(0) [relinquish to any other waiting threads] does not
fix the problem.  With Sleep(1), I can run my SDS.exe executable outside the
debugger, and get this:

SDS 940 simulator V4.0-0 Beta        git commit id: $Format:
sim> attach mux 23
Listening on port 23
sim>

I'm not enough of a networking guy to debug this further, nor to I feel
confident about committing this change. I'll let others more knowledgeable
take it from here.  FYI, here's the SHOW VER info:

sim> show ver
SDS 940 simulator V4.0-0 Beta
        Simulator Framework Capabilities:
                32b data
                32b addresses
                no Ethernet
                Idle/Throttling support is available
                Virtual Hard Disk (VHD) support
                RAW disk and CD/DVD ROM support
        Host Platform:
                Compiler: Microsoft Visual C++ 16.00.40219.01
                Simulator Compiled: Feb 21 2014 at 18:30:41
                Memory Access: Little Endian
                Memory Pointer Size: 32 bits
                Large File (>2GB) support
                OS clock tick size: 1ms
                OS: Windows:
Microsoft Windows XP [Version 5.1.2600]
                x86 Family 6 Model 15 Stepping 10, GenuineIntel -
x86-%PROCESSOR_ARCHITEW6432%

        git commit id: $Format:
sim>

This is the ONLY change I've made to the sim*.* and scp*.* files.  I have
made a number of changes to the sds*.* files fixing bugs in the course of
getting the SDS 940 TSS monitor and exec running, but I'll post or commit
those later, when I'm further along.

Saludos,
Mark Emmer
Michoacán, Mexico