Final answer:
When writing to a TCP socket, data goes into an application buffer, then to a socket buffer, and is managed by the TCP protocol before being sent.
Step-by-step explanation:
When an application writes to a TCP socket, several buffers are involved in the process. These buffers are part of the TCP stack's operation and are created by the operating system to manage data transmission.
The first buffer is the application buffer, where data is stored before it is sent through the socket. The application writes data to this buffer, which can then be transferred to the socket buffer by the system calls made through the network API.
Once the data moves to the socket buffer, it is managed by the operating system's networking stack. Here, the data awaits to be acknowledge by the TCP protocol before actually being sent across the network. The TCP protocol manages data transfer reliability, flow control, and congestion avoidance ensuring that data arrives correctly at the destination.