PR_OpenTCPSocket 编辑

Creates a new TCP socket of the specified address family.

Syntax

#include <prio.h>

/wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PRFileDesc* PR_OpenTCPSocket(PRIntn af);

Parameters

The function has the following parameters:

af

The address family of the new TCP socket. Can be PR_AF_INET (IPv4), PR_AF_INET6 (IPv6), or PR_AF_LOCAL (Unix domain, supported on POSIX systems only).

Returns

The function returns one of the following values:

• Upon successful completion, a pointer to the /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PRFileDesc object created for the newly opened TCP socket.
• If the creation of a new TCP socket failed, NULL.

Description

TCP (Transmission Control Protocol) is a connection-oriented, reliable byte-stream protocol of the TCP/IP protocol suite. PR_OpenTCPSocket creates a new TCP socket of the address family af. A TCP connection is established by a passive socket (the server) accepting a connection setup request from an active socket (the client). Typically, the server binds its socket to a well-known port with /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Bind, calls /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Listen to start listening for connection setup requests, and calls /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Accept to accept a connection. The client makes a connection request using /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Connect.

After a connection is established, the client and server may send and receive data between each other. To receive data, one can call /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Read or /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Recv. To send data, one can call /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Write, /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Writev, /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Send, or /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_TransmitFile. /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_AcceptRead is suitable for use by the server to accept a new client connection and read the client's first request in one function call.

A TCP connection can be shut down by /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Shutdown, and the sockets should be closed by /wiki/en-US/docs/Mozilla/Projects/NSPR/Reference/PR_Close.