From: Matthew Bloch <mattbee@...>
Date: 2002-05-06T18:33:56+09:00
Subject: getaddrinfo failing under Win32

  [originally posted to the comp.os.ms.programmer.win32 newsgroup, but
   reposted here in case it's a Ruby-specific problem]

Hi there; I'm finishing off a trivia game written in the Ruby language 
(www.ruby-lang.org) which will be running atop Windows NT/2000.  Because 
the game is written in an interpreted language, the test versions of the 
game could be launched with a batch file which just reads:

  ruby-win32\rubyw.exe -r data_england -Igame -Iruby-win32 game\main.rb

And the ruby-win32 directory contains all the necessary .DLLs and support 
libraries for the Ruby runtime.  This works fine and the game launches.  
However, the software platform on which this is based demands that the 
'runnable' part of the game be a single executable, so I figured I should 
write a simple launcher program which would execute a command defined in a 
text file.  So I came up with this:

  #include <windows.h>
  #include <stdio.h>

  int APIENTRY WinMain(HINSTANCE hInstance,
                       HINSTANCE hPrevInstance,
                       LPSTR     lpCmdLine,
                       int       nCmdShow)
  {
      STARTUPINFO startupInfo;
      PROCESS_INFORMATION procInfo;
      BOOL success;
      FILE *fh;
      char cmd[512];
      int r;

      fh = fopen("cmd.txt", "r");
      if (fh == NULL)
          return 0;
      r = fread(cmd, 1, 512, fh);    
      fclose(fh);

      r--;
      while (cmd[r] < 32)
          r--;
      cmd[r+1] = 0;
    
      GetStartupInfo(&startupInfo);

      success = CreateProcess(NULL, cmd,
                              NULL, NULL, FALSE,
                              0, (char*) "PATH=ruby-win32\0\0",
                              NULL,
                              &startupInfo,
                              &procInfo);
    
      if (success)
          WaitForSingleObject(procInfo.hProcess, INFINITE);
    
      return 0;
  }

Which I compiled with:

  /usr/local/mingw32/bin/i386-mingw32-msvc-gcc \
    -mwindows -o Launcher.exe Launcher.c

And it seems to work fine if I try to run notepad, other Ruby scripts etc. 
by putting the command line string into cmd.txt and running Launcher.exe . 

However, the application needs to start a TCP server process, and part of 
this requires a call to getaddrinfo (TCPServer.new in Ruby).  My problem is 
that this call succeeds when I launch the Ruby interpreter through a batch 
file, or at the command line, but fails with the error message "ai_family 
not supported" when launched through my launcher program.

I'm fairly new to the Win32 API, so I'd appreciate any insight as to why 
this happens (on Windows 2000); is it due to a security restriction imposed 
on the child process?

thanks,

-- 
Matthew