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multi-threaded socket communication problem

lll888 asked
Hi there,

In my app, I need to open many threads which all connect to a same server and same port, reading and writing data at the same time. But the problem is that after some time of execution, I got error something like "ESocketError: maximum number of sockets allowed....", it seems that if there's too many threads(actually over 10 or so), then it won't let me connect.

I use TClientSocket to do the socket communication. So i'd like to ask why I am getting this error? Is there any limit on number of threads connecting to a same server and port number?

Thanks for any input.
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What OS are you running on? Is the server on the same machine as the client?


i am running on Win2k, no, the server is a remote one, actually it's a mail server. I used tcp/ip to make a direct connection to it. If i use only 1 thread, it works alright, but if I use many threads, i always got that error.
Ok, this takes away several possibilities for the cause and practically eliminates your machine or application as problem source.

Note that most mail servers are configured in such a way that they only accept a certain number of simultaneous connections from one specific host. That's because like this the possibilities for spamming or DOS attacks are limited. So your next step would probably be to ask the postmaster of this mail server for limitations of their service.

are you creating thos sockets connection dynamicly? if the answer is yes... then... did you realease each one of them?

"ESocketError: maximum number of sockets allowed" sounds more a local problem than a server problem, however what kind of server are you connecting to (email, web, or custom)
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