一个简单点的阻塞式tcp服务器如下所示：
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#include <stdio.h>#include <string.h>#include <sys/socket.h>#include <netinet/in.h> int main(int
argc, char**argv){ int
listenfd,connfd,n, ret; struct
sockaddr_in servaddr, cliaddr; socklen_t clilen; pid_t childpid; char
mesg[1000], *peeraddr; listenfd = socket(AF_INET, SOCK_STREAM, 0); if
(listenfd < 0) { printf("create socket error\n"); return
-1; } printf("create socket success\n"); memset(&servaddr, 0, sizeof(servaddr)); servaddr.sin_family = AF_INET; servaddr.sin_addr.s_addr = htonl(INADDR_ANY); servaddr.sin_port = htons(6789); ret = bind(listenfd, (struct
sockaddr *)&servaddr, sizeof(servaddr)); if
(ret == -1) { printf("bind error\n"); return
-1; } printf("bind success\n"); ret = listen(listenfd, 1024); if
(ret == -1) { printf("listen error\n"); return
-1; } printf("listening...\n"); for
(;;) { clilen = sizeof(cliaddr); connfd = accept(listenfd, (struct
sockaddr *)&cliaddr, &clilen); printf("Accept request from %s\n", inet_ntoa(cliaddr.sin_addr)); n = read(connfd, mesg, 1000); if
(n < 0) { printf("read error!\n"); } printf("Received:%s\n", mesg); close(connfd); }} |
编译期间没有遇到问题。运行的时候程序在47行收到了segment fault错误。用man手册查看inet_ntoa，调用方式如下：
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char
*inet_ntoa(struct
in_addr in); |
cliaddr的类型定义是：
struct sockaddr_in { /* in netinet/in.h */
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<em id="__mceDel"> sa_family_t sin_family; in_port_t sin_port; struct
in_addr sin_addr; unsigned char
sin_zero[sizeof(struct
sockaddr) - sizeof(sa_family_t) - sizeof(in_port_t), sizeof(struct
in_addr)];};</em> |
乍一看，没什么问题啊，怎么会出现段错误呢？
捣腾了半天，才发现是缺少了inet_ntoa所在的头文件 arpa/inet.h，包含该头文件即可。好坑。
inet_ntoa 的一个小问题,布布扣,bubuko.com
原文：http://www.cnblogs.com/cobbliu/p/3781558.html