badserver socket

代码是《linux高级程序设计》第5章的内容

mqq@208_181:~/fabricehao/test/20120726> cat errtcpserver.c 
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
int main(int args,char * argv){

    int i,s,fd,len;
    struct sockaddr_in my_addr;
    struct sockaddr_in remote_addr;
    int sin_size;
    char buf[BUFSIZ];
    memset(&my_addr,0,sizeof(my_addr));
    my_addr.sin_family=AF_INET;
    my_addr.sin_addr.s_addr=INADDR_ANY;
    unsigned int pp=87654;
    my_addr.sin_port=htons(pp);
    if((s=socket(AF_INET,SOCK_STREAM,0))<0){
        perror("socket");
        return 1;
    }
    if(bind(s,(struct sockaddr *)&my_addr,sizeof(struct sockaddr))<0){
        perror("bind");
        return 1;
    }
    listen(s,5);
    sin_size=sizeof(struct sockaddr_in);
    if((fd=accept(s,(struct sockaddr *)&remote_addr,&sin_size))<0)
    {
        perror("accept");
        return 1;
    }
    printf("accept client %s\n",inet_ntoa(remote_addr.sin_addr));
    len=send(fd,"welcome to my server\n",21,0);
    for(i=0;i<5;i++){
        len=recv(fd,buf,BUFSIZ,0);
        buf[len]='\0';
        printf("%s\n",buf);
    }
    close(fd);
    close(s);
    return 0;
}

mqq@208_181:~/fabricehao/test/20120726> cat badclient.c 
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
int main(args,argv){
    int i,s,fd,len;
    struct sockaddr_in remote_addr;
    int sin_size;
    char buf[BUFSIZ];
    memset(&remote_addr,0,sizeof(remote_addr));
    remote_addr.sin_family=AF_INET;
    remote_addr.sin_addr.s_addr=inet_addr("127.0.0.1");
     unsigned int pp=87654;
    remote_addr.sin_port=htons(pp);
    if((s=socket(AF_INET,SOCK_STREAM,0))<0){
        perror("socket");
        return 1;
    }
    if(connect(s,(struct sockaddr *)&remote_addr,sizeof(struct sockaddr))<0){
        perror("connect");
        return 1;
    }
    printf("connect to server");
    len=recv(s,buf,BUFSIZ,0);
    buf[len]='\0';
    printf("%s",buf);
    len=send(s,"test1 message",13,0);
    len=send(s,"test2 message",13,0);
    len=send(s,"test3 message",13,0);
    len=send(s,"test4 message",13,0);
    len=send(s,"test5 message",13,0);
    close(s);
    return 0;
}

betterserver.c
len=recv(fd,buf,13,0);指定了缓冲

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
int main(int args,char * argv){

    int i,s,fd,len;
    struct sockaddr_in my_addr;
    struct sockaddr_in remote_addr;
    int sin_size;
    char buf[BUFSIZ];
    memset(&my_addr,0,sizeof(my_addr));
    my_addr.sin_family=AF_INET;
    my_addr.sin_addr.s_addr=INADDR_ANY;
    unsigned int pp=87654;
    my_addr.sin_port=htons(pp);
    if((s=socket(AF_INET,SOCK_STREAM,0))<0){
        perror("socket");
        return 1;
    }
    if(bind(s,(struct sockaddr *)&my_addr,sizeof(struct sockaddr))<0){
        perror("bind");
        return 1;
    }
    listen(s,5);
    sin_size=sizeof(struct sockaddr_in);
    if((fd=accept(s,(struct sockaddr *)&remote_addr,&sin_size))<0)
    {
        perror("accept");
        return 1;
    }
    printf("accept client %s\n",inet_ntoa(remote_addr.sin_addr));
    len=send(fd,"welcome to my server\n",21,0);
    for(i=0;i<5;i++){
        len=recv(fd,buf,13,0);
        buf[len]='\0';
        printf("%s\n",buf);
    }
    close(fd);
    close(s);
    return 0;
}

liburl使用

mqq@208_181:~/fabricehao/test/20120726> cat liburl.c 
#include <stdio.h>
#include <curl/curl.h>
int main(int args,char * argv){
    CURL * curl;
    CURLcode res;
    curl =curl_easy_init();
    if(!curl)
    {
        perror("curl");
        return 1;
    }
    curl_easy_setopt(curl,CURLOPT_URL,argv[1]);
    curl_easy_setopt(curl,CURLOPT_PROXY,"webproxy:8080");
    res=curl_easy_perform(curl);

    curl_easy_cleanup(curl);
    return 0;
}

yum install libcurl-devel  
这个是依赖
gcc -I /usr/local/include/ -o getweb liburl.c -lcurl