A socket in several threads

This is an academical question. I'm satudying Telecommunications and tomorrow I have an exam about Concurrent Programming.
My questions is quite simple and you can ommit this introduction about what is the exercise if you prefer.
We have seen some ways to pass messages between threads. Once we use an active monitor to take control over the mutex. In this case the active monitor consists of a simple Thread which answers proxys threads petitons for accesing to the mutex. To communicate with the Active Monitor we use s-pipes, which are just a pair of sockets connected where you send messages from one socket and read them from the other. For example we have an array of two sockets, connected: data[0] and data[1].
The proxys thread have all of them the socket data[0] that they use for sending petitions in accesing mutex to the Active Monitor. Anything wrong till here?
We use a BufferedReader (I think) for sending messages through the socket.
Question: Can all these threads use this socket to send petitions without synchronizing it?

That's not a problem. I didn't explain all the things which are involved in the program. The Control Thread doesn't answer through the same s-pipe.
So if T1 and T2 ask for acces to mutex, they wait until they recieve a responsen in an another s-pipe only dedicated for each of them. The s-pipe I called data[0] and data[1] is used just for sending requests and nothing else.
So there are:
- A pair of sockets for sending petitions to Control Thread, they are used only in one way. In this case data[0] is the socket in the proxys threads (T1, T2, ....) and data[1] is the socket in the Control Thread.
- A pair of sockets for each proxy thread, for answering petitions of all the Proxy Threads. For example. If we have 3 proxy threads: T1, T2 and T3. There are then: RecieveAskT1[1] which is in T1; RecieveAskT1[0] which is in Control Thread.
RecieveAskT2[1] which is in T1; RecieveAskT2[0] which is in Control Thread.
RecieveAskT3[1] which is in T1; RecieveAskT3[0] which is in Control Thread.
So the problem is with the socket data[0] which is used for T1, T2,...
What is important for me is: if some of the methods which are involved in sending "things" through a socket are synchronized? Otherwise I cannot understand how my professer uses data[0] without protecting it against the scheduler.
Previous thanks for you future answer!

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