我在编译C程序时出错了

Question

我正在尝试编译这个C程序，但我得到这个消息

warning: passing 'int *' to parameter of type 'socklen_t *'
(aka 'unsigned int *') converts between pointers to integer types with
different sign [-Wpointer-sign]
if ((new_s = accept(s, (struct sockaddr *) &sin, &addr_len)) < 0) {
^~~~~~~~~

有人能帮帮我吗?

#include<string.h>
#include<stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <fcntl.h> // for open
#include <unistd.h> // for close
#define SERVER_PORT 5432
#define MAX_PENDING 5
#define MAX_LINE 256
int main()
{
struct sockaddr_in sin;
char buf[MAX_LINE];
int buf_len, addr_len;
int s, new_s;
/* build address data structure */
bzero((char *)&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = INADDR_ANY;
sin.sin_port = htons(SERVER_PORT);
/* setup passive open */
if ((s = socket(PF_INET, SOCK_STREAM, 0)) < 0) {
perror("simplex-talk: socket");
exit(1);
}
if ((bind(s, (struct sockaddr *)&sin, sizeof(sin))) < 0) {
perror("simplex-talk: bind");
exit(1);
}
listen(s, MAX_PENDING);
/* wait for connection, then receive and print text */
while(1) {
if ((new_s = accept(s, (struct sockaddr *) &sin, &addr_len)) < 0) {
perror("simplex-talk: accept");
exit(1);
}
while (buf_len == recv(new_s, buf, sizeof(buf), 0))
fputs(buf, stdout);
close(new_s);
}
}

Answer 1

正如错误消息所述，当函数期望该参数为socklen_t *时，您正在将int *参数传递给accept作为最后一个参数。

将addr_len的类型改为socklen_t。