我正在嘗試編寫一個偵聽我的機器上的端口的C程序。 我遇到了一個奇怪的錯誤。綁定失敗:無法分配請求的地址
每當我嘗試將套接字綁定到固定IP(127.0.0.1
或我的實際IP)時,出現"bind failed: Cannot assign requested address"
錯誤。 但是,當我將INADDR_ANY
傳遞給綁定爲綁定的地址時,它起作用。
這些是我擁有的唯一兩個IP,所以它不能是0.0.0.0,因爲我有一些其他IP地址可用。
下面是代碼:
#include<sys/types.h>
#include<stdio.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<errno.h>
#include<stdlib.h>
#include<string.h>
int main()
{
int port = 1234; /* port number */
int rqst; /* socket accepting the request */
socklen_t alen; /* length of address structure */
struct sockaddr_in my_addr; /* address of this service */
struct sockaddr_in client_addr; /* client's address */
int sockoptval = 1;
int svc;
/* create a TCP/IP socket */
if ((svc = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
perror("cannot create socket");
exit(1);
}
/* allow immediate reuse of the port */
setsockopt(svc, SOL_SOCKET, SO_REUSEADDR, &sockoptval, sizeof(int));
/* bind the socket to our source address */
memset((char*)&my_addr, 0, sizeof(my_addr)); /* 0 out the structure */
my_addr.sin_family = AF_INET; /* address family */
my_addr.sin_port = htons(port);
//my_addr.sin_addr.s_addr = htonl(INADDR_ANY); /* Works! */
my_addr.sin_addr.s_addr = htonl(inet_addr("127.0.0.1")); /* Fails! */
if (bind(svc, (struct sockaddr *)&my_addr, sizeof(my_addr)) < 0) {
perror("bind failed");
exit(1);
}
printf("Listening on %d\n", my_addr.sin_addr.s_addr);
/* set the socket for listening (queue backlog of 5) */
if (listen(svc, 5) < 0) {
perror("listen failed");
exit(1);
}
/* loop, accepting connection requests */
for (;;) {
while ((rqst = accept(svc, (struct sockaddr *)&client_addr, &alen)) < 0) {
/* we may break out of accept if the system call */
/* was interrupted. In this case, loop back and */
/* try again */
if ((errno != ECHILD) && (errno != ERESTART) && (errno != EINTR)) {
perror("accept failed");
exit(1);
}
}
/* the socket for this accepted connection is rqst */
}
}
不要綁定一個IP:端口組合,而不是一個IP? netstat不會將端口1234顯示爲綁定到任何進程。 – ffledgling 2013-03-18 22:25:28