I have a CGI [client] written in VC++ 5.0 that is used to access a file and transmit it to a remote machine [server]. For small files (less than 5k) the CGI works fine, but when I send files larger than 5k (very rough figure -- larger than 4096 though ;-) the message simply disappears. There are no socket errors of any kind. The message quietly finds its way to the bit bucket. setsockopt is used to set the send buffer size to 200K.
I'm looking into obtaining a socket monitor utility but since this is at work I have to go through some red tape before I can implement it. If anyone has any ideas or any experience with a problem similar to this, I'm all ears! Source code is not entirely available, but I can share fragments for investigation purposes.