看了TCP的一些东西,知道服务器往以及关闭了的sockfd中写两次时,会产生SIGPIPE信号,如果不处理,默认会挂掉服务器
弄个小例子测试一下:
#include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <stdio.h> #include <fcntl.h> #include <sys/wait.h> #include <netinet/in.h> #include <errno.h> #include <signal.h> #include <unistd.h> #include <stdlib.h> #include <sys/socket.h> #include <signal.h> #define ERR_EXIT(m) do { perror(m); exit(EXIT_FAILURE); }while(0) void handle(int arg) { printf("sigpipe\n"); } int main(int argc, const char *argv[]) { signal(SIGPIPE, handle);//SIGPIPE信号的处理 int sockfd = socket(AF_INET, SOCK_STREAM, 0); if(sockfd == -1) ERR_EXIT("socket"); struct sockaddr_in seraddr; seraddr.sin_family = AF_INET; seraddr.sin_port = htons(8888); seraddr.sin_addr.s_addr = inet_addr("127.0.0.1") ; socklen_t len = sizeof(seraddr); if(-1 == (bind(sockfd, (struct sockaddr*)&seraddr, len))) ERR_EXIT("bind"); if(listen(sockfd, 3) == -1) ERR_EXIT("listen"); int clientfd = accept(sockfd, NULL, NULL); printf("client\n"); while(1) { sleep(3); printf("hello\n"); write(clientfd, "hello", sizeof("hello")); } return 0; }
客户端使用telnet连接
发现:
当客户端关闭后,服务器端还会写两次后,就会收到SIGPIPE信号,后续继续会收到此信号
telnet localhost 8888
--》客户端:
[email protected] ~]$ telnet localhost 8888 Trying ::1... telnet: connect to address ::1: Connection refused Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. hello hello hello ^] telnet> Connection closed.
服务器信息:
? mianshi git:(master) ? ./a.out client hello hello hello hello //-》对方会发送一个RST复位报文 hello sigpipe hello sigpipe //-->是由于write导致的 hello sigpipe hello sigpipe ^C
可以看到是在客户端关闭后,再发送 第2个信息后才收到的SIFPIPE信号
后续发送仍然会收到SIGPIPE信号
时间: 2024-10-16 15:51:07