Linux下调用getaddrinfo失败
在学习APUE第16章关于网络IPC：套接字时，运行程序清单16-5时失败，错误信息如下：
[ajaxhe@localhost sockets]$ ./ruptimed
ruptimed: getaddrinfo error: Servname not supported for ai_socktype
错误是来自getaddrinfo()函数调用失败，单从错误输出来看，是server name出了问题，请问下这个问题改如何解决？
源代码如下：
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <sys/socket.h>
#include <netdb.h>
#include <errno.h>
#define BUFLEN 128
#define QLEN 10
#ifndef HOST_NAME_MAX
#define HOST_NAME_MAX 256
#endif
extern int initserver(int, struct sockaddr *, socklen_t , int);
void
serve(int sockfd)
{
int clfd;
FILE *fp;
char buf[BUFLEN];
for(;;) {
clfd = accept(sockfd, NULL, NULL);
if(clfd < 0) {
syslog(LOG_ERR, "ruptime: accept error:%s",
strerror(errno));
exit(1);
}
if((fp = popen("/usr/bin/uptime", "r")) == NULL) {
sprintf(buf, "error:%s\n", strerror(errno));
send(clfd, buf, strlen(buf), 0);
} else {
while(fgets(buf, BUFLEN, fp) != NULL)
send(clfd, buf, strlen(buf), 0);
pclose(fp);
}
close(clfd);
}
}
int
main(int argc, char *argv[])
{
struct addrinfo *ailist, *aip;
struct addrinfo hint;
int sockfd, err, n;
char *host;
if(argc != 1) {
printf("usage: ruptimed");
exit(1);
}
#ifdef _SC_HOST_NAME_MAX
n = sysconf(_SC_HOST_NAME_MAX);
if(n < 0)
#endif
n = HOST_NAME_MAX;
host = malloc(n);
if(host == NULL) {
perror("malloc error");
exit(1);
}
/* daemonize("ruptimed"); */
hint.ai_flags = AI_CANONNAME;
hint.ai_family = 0;
hint.ai_socktype = SOCK_STREAM;
hint.ai_protocol = 0;
hint.ai_addrlen = 0;
hint.ai_canonname = NULL;
hint.ai_next = NULL;
if((err = getaddrinfo(host, "ruptime", &hint, &ailist)) != 0) {
syslog(LOG_ERR, "ruptimed: getaddrinfo error: %s", gai_strerror(err));
exit(1);
}
for(aip = ailist; aip != NULL; aip = aip->ai_next) {
if((sockfd = initserver(SOCK_STREAM, aip->ai_addr, aip->ai_addrlen, QLEN)) >= 0) {
serve(sockfd);
exit(0);
}
}
exit(1);
}
BorisX
11 years, 9 months ago
