[lwip-users] Problem with closing TCP socket

Hi,

I am using lwIP 1.3.1 and have developed an application which has been running successfully for several months.

The application is a TCP server with the PC running as a client.

I have recently discovered a problem if the communications link is broken, either at the unit end or the PC, my unit fails to reconnect with the host when the link is re-established.

This seems to occur more readily if communications between the units was active at the time the link was broken.

I have a background timer running checking for communications inactivity which closes the TCP connection after a period of no communications.

Can anyone tell me how to correctly close the TCP connection cleanly, so that it can recover?

I am calling tcp_close( pcb ) routine, is this correct?

Why does the failure to reconnect seem to occur when communications are active?

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From:	Carr, Anthony
Subject:	[lwip-users] Problem with closing TCP socket
Date:	Tue, 27 Nov 2012 15:40:15 +0000