tcp的socket的helloworld

想弄个东西
socket＋shm＋epoll，想弄个比nginx还快还简单点东西
顺便学一下c的这些宝贝


今天现把nginx的注释都看一遍吧
对于nginx1.0.10
find . -name *.c |xargs grep "/\*.*\*/"|wc -l
2577行
似乎这样更多一些
find . -name *.c |xargs grep "/\*.*"|wc -l
3206
看出ngx_inet.c 是关于socket的，学习一下吧



－－－－－－－－－－－－－－－－－－－－－－－－－－－－－普通的socket例子
看看server干了什么
/* Create the TCP socket */
/* Construct the server sockaddr_in structure */
/* Bind the server socket */
/* Listen on the server socket */
/* Run until cancelled */
    /* Receive message */
    /* Send bytes and check for more incoming data in loop */
close


看看client干了什么
/* Create the TCP socket */
/* Construct the server sockaddr_in structure */
/* Establish connection */
/* Send the word to the server */
    /* Receive the word back from the server */
close

sh-3.2# cat TCPechoServer.c 
#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <netinet/in.h>

#define MAXPENDING 5    /* Max connection requests */
#define BUFFSIZE 32
void Die(char *mess) { perror(mess); exit(1); }
void HandleClient(int sock) {
		char buffer[BUFFSIZE];
		int received = -1;
		/* Receive message */
		if ((received = recv(sock, buffer, BUFFSIZE, 0)) < 0) {
				Die("Failed to receive initial bytes from client");
		}
		/* Send bytes and check for more incoming data in loop */
		while (received > 0) {
				/* Send back received data */
				if (send(sock, buffer, received, 0) != received) {
						Die("Failed to send bytes to client");
				}
				/* Check for more data */
				if ((received = recv(sock, buffer, BUFFSIZE, 0)) < 0) {
						Die("Failed to receive additional bytes from client");
				}
		}
		close(sock);
}
int main(int argc, char *argv[]) {
            int serversock, clientsock;
            struct sockaddr_in echoserver, echoclient;

            if (argc != 2) {
              fprintf(stderr, "USAGE: echoserver <port>\n");
              exit(1);
            }
            /* Create the TCP socket */
            if ((serversock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
              Die("Failed to create socket");
            }
            /* Construct the server sockaddr_in structure */
            memset(&echoserver, 0, sizeof(echoserver));       /* Clear struct */
            echoserver.sin_family = AF_INET;                  /* Internet/IP */
            echoserver.sin_addr.s_addr = htonl(INADDR_ANY);   /* Incoming addr */
            echoserver.sin_port = htons(atoi(argv[1]));       /* server port */
			 /* Bind the server socket */
			if (bind(serversock, (struct sockaddr *) &echoserver,
									sizeof(echoserver)) < 0) {
					Die("Failed to bind the server socket");
			}
			/* Listen on the server socket */
			if (listen(serversock, MAXPENDING) < 0) {
					Die("Failed to listen on server socket");
			}
			 /* Run until cancelled */
			while (1) {
					unsigned int clientlen = sizeof(echoclient);
					/* Wait for client connection */
					if ((clientsock =accept(serversock, (struct sockaddr *) &echoclient,
													&clientlen)) < 0) {
							Die("Failed to accept client connection");
					}
					fprintf(stdout, "Client connected: %s\n",
									inet_ntoa(echoclient.sin_addr));
					HandleClient(clientsock);
			}
}
sh-3.2# 

h-3.2# cat TCPecho.c 
#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <netinet/in.h>

#define BUFFSIZE 32
void Die(char *mess) {
	perror(mess);
 	exit(1);
}
int main(int argc, char *argv[]) {
		int sock;
		struct sockaddr_in echoserver;
		char buffer[BUFFSIZE];
		unsigned int echolen;
		int received = 0;

		if (argc != 4) {
				fprintf(stderr, "USAGE: TCPecho <server_ip> <word> <port>\n");
				exit(1);
		}
		/* Create the TCP socket */
		if ((sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
				Die("Failed to create socket");
		}
 /* Construct the server sockaddr_in structure */
        memset(&echoserver, 0, sizeof(echoserver));       /* Clear struct */
        echoserver.sin_family = AF_INET;                  /* Internet/IP */
        echoserver.sin_addr.s_addr = inet_addr(argv[1]);  /* IP address */
        echoserver.sin_port = htons(atoi(argv[3]));       /* server port */
        /* Establish connection */
        if (connect(sock,
                    (struct sockaddr *) &echoserver,
                    sizeof(echoserver)) < 0) {
          Die("Failed to connect with server");
        }
  /* Send the word to the server */
        echolen = strlen(argv[2]);
        if (send(sock, argv[2], echolen, 0) != echolen) {
          Die("Mismatch in number of sent bytes");
        }
        /* Receive the word back from the server */
        fprintf(stdout, "Received: ");
        while (received < echolen) {
          int bytes = 0;
          if ((bytes = recv(sock, buffer, BUFFSIZE-1, 0)) < 1) {
            Die("Failed to receive bytes from server");
          }
          received += bytes;
          buffer[bytes] = '\0';        /* Assure null terminated string */
          fprintf(stdout, buffer);
        }
		fprintf(stdout, "\n");
        close(sock);
        exit(0);    
}            
sh-3.2#