From: Wai-Sun Chia <waisun.chia@...>
Date: 2001-07-10T16:09:15+09:00
Subject: [ruby-talk:17595] Re: low-level TCP/IP manipulations?

Al Chou wrote:

> Hi, all,
> 
> This question may be naive or just plain stupid, but searching the list archive
> for "TCP" and "IP" didn't turn up anything that looked relevant, so here goes.
> 
> I'm testing some network hardware and software and (think I) need to be able to
> manipulate TCP and/or IP at kind of a low level.  For instance, one of my test
> cases includes the requirement "device should return a TCP/IP No Listener error
> code".  I'm writing an emulator for this device in Ruby and wondering whether I
> can get such fine-grained control over network communications from within Ruby.
> 


What you want is ECONNREFUSED (see connect(2)) return code, which 
unfortunately is not returned in Ruby/Socket.

socket.c

    754     if (status < 0) {
    755         switch (errno) {
    756           case EAGAIN:
    757 #ifdef EINPROGRESS
    758           case EINPROGRESS:
    759 #endif
    760         thread_write_select(fd);
    761         continue;
    762 
    763 #ifdef EISCONN
    764           case EISCONN:
    765         status = 0;
    766         errno = 0;
    767         break;
    768 #endif
    769         }
    770     }


What you can do is just add additional case statements for the switch 
construct and you're off, f'rinstance:

switch (errno) {
    case EAGAIN:
         :
    case ECONNREFUSED:
       break;
    case EBADF:
       break;

etc. etc.

Recompile Ruby and test...
Let us know.

-- 
Wai-Sun "Squidster" Chia
Unix/Web Developer/RHCE
Professional Services