I get the following socket exceptions from tcpClient test applications
when running them on a SOLARIS 2.6 System and communicating with a tcpServer
test application running on a WINDOWS 95 System. This problem is highly
reproducible.

java.net.SocketException: Operation already in progress
java.net.SocketException: Transport endpoint is already connected

I get a [java.net.SocketException: Operation already in progress] or a
[java.net.SocketException: Transport endpoint is already connected]
exception from [java.net.PlainSocketImpl.socketConnect(Native Method)]
when I repeatedly run tcpClient test applications on a SOLARIS 2.6 System
communicating with a tcpServer test application running on a WINDOWS 95
system. The tcpClient test applications die with the socket exception.

When running the same tcpClient test applications in reverse on a
WINDOWS 95 System and communicating with a tcpServer test application
running on a SOLARIS 2.6 System I don't see the problem.

When running both the tcpClient test application and the tcpServer
test application on a SOLARIS 2.6 System I don't see the problem.

When running both the tcpClient test application and the tcpServer
test application on a WINDOWS 95 System I don't see the problem.

Here is a summary of the configurations and what PASSES and FAILS. The
only configuration that fails is tcpClients running on SOLARIS 2.6 and
communicating with the tcpServer running on WINDOWS 95.

SOLARIS 2.6 SOLARIS 2.6
tcpClient1, tcpClient2 --------> tcpServer PASSES

WINDOWS 95 WINDOWS 95
tcpClient1, tcpClient2 --------> tcpServer PASSES

SOLARIS 2.6 WINDOWS 95
tcpClient1, tcpClient2 --------> tcpServer FAILS

WINDOWS 95 SOLARIS 2.6
tcpClient1, tcpClient2 --------> tcpServer PASSES

The tcpClient test application repeatedly does the following:

for i = 1 to loopcount
do
open a socket connection to the tcpServer on port 30000
for j = 1 to messagecount
do
write a message to the tcpServer
read message back from the tcpServer
verify that the message read back matches the message
that was wriitem
done
close the socket connection to the tcpServer
done

The following invocations will reproduce this problem:

----------------------------
On WINDOWS 95 System (aefpc)
----------------------------
aefpc> java tcpServer -d -v -l 0

----------------------------
On SOLARIS 2.6 System (lobo)
----------------------------
lobo> java tcpClient -v -b 64 -l 1000 -s aefpc -c -m 10 -p 30000
lobo> java tcpClient -v -b 16 -l 1000 -s aefpc -c -m 10 -p 30000
... ... ...
... ... ...
... ... ...
VERBOSE: completed session loop #219
VERBOSE: connect to server aefpc at port 30000
VERBOSE: completed session loop #220
VERBOSE: connect to server aefpc at port 30000
VERBOSE: completed session loop #221
VERBOSE: connect to server aefpc at port 30000
ERROR: tcpClient.tcpClient(): exception occurred:
java.net.SocketException: Operation already in progress
java.net.SocketException: Operation already in progress
        at java.net.PlainSocketImpl.socketConnect(Native Method)
        at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:297)
        at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:131)
        at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:118)
        at java.net.Socket.<init>(Socket.java:223)
        at java.net.Socket.<init>(Socket.java:91)
        at tcpClient.<init>(tcpClient.java:104)
        at tcpClient.main(tcpClient.java:83)


lobo> java tcpClient -v -b 64 -l 1000 -s aefpc -c -m 10 -p 30000
lobo> java tcpClient -v -b 16 -l 1000 -s aefpc -c -m 10 -p 30000
... ... ...
... ... ...
... ... ...
VERBOSE: completed session loop #106
VERBOSE: connect to server aefpc at port 30000
VERBOSE: completed session loop #107
VERBOSE: connect to server aefpc at port 30000
ERROR: tcpClient.tcpClient(): exception occurred:
java.net.SocketException: Transport endpoint is already connected
java.net.SocketException: Transport endpoint is already connected
        at java.net.PlainSocketImpl.socketConnect(Native Method)
        at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:297)
        at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:131)
        at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:118)
        at java.net.Socket.<init>(Socket.java:223)
        at java.net.Socket.<init>(Socket.java:91)
        at tcpClient.<init>(tcpClient.java:104)
        at tcpClient.main(tcpClient.java:83)

I added the TCP Client/Server Test Application as part of the attachments. Benjamin use this version because I made some changes and modifications.

This is an update to this bug. I saw the same socket exception from SOLARIS 2.6 to SOLARIS 2.6 when running a TCP stress scenario. It is not easy to reproduce however like under WINDOWS 95.