我通过引用here上的网页在底部使用代码ntp客户端代码。代码接收时间信息,然后我想将时间信息存储为YYYYMMDDHHMM
,如201304211405
。代码接收来自NTP服务器的时间信息,但是我很难找到如何将该信息传递给strftime
,我应该如何将接收到的时间信息传递给strftime
?从NTP服务器向strftime函数传递时间信息
下面是代码
i=recv(s,buf,sizeof(buf),0);
tmit=ntohl((time_t)buf[10]); //# get transmit time
tmit-= 2208988800U;
printf("tmit=%d\n",tmit);
//#compare to system time
printf("Time is time: %s",ctime(&tmit));
char buffer[13];
struct tm * timeinfo;
timeinfo = ctime(&tmit);
strftime (buffer,13,"%04Y%02m%02d%02k%02M",timeinfo);
printf("new buffer:%s\n" ,buffer);
这里的相关部分,我使用
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
void ntpdate();
int main() {
ntpdate();
return 0;
}
void ntpdate() {
char *hostname="79.99.6.190 2";
int portno=123; //NTP is port 123
int maxlen=1024; //check our buffers
int i; // misc var i
unsigned char msg[48]={010,0,0,0,0,0,0,0,0}; // the packet we send
unsigned long buf[maxlen]; // the buffer we get back
//struct in_addr ipaddr; //
struct protoent *proto; //
struct sockaddr_in server_addr;
int s; // socket
int tmit; // the time -- This is a time_t sort of
//use Socket;
proto=getprotobyname("udp");
s=socket(PF_INET, SOCK_DGRAM, proto->p_proto);
memset(&server_addr, 0, sizeof(server_addr));
server_addr.sin_family=AF_INET;
server_addr.sin_addr.s_addr = inet_addr(hostname);
server_addr.sin_port=htons(portno);
// send the data
i=sendto(s,msg,sizeof(msg),0,(struct sockaddr *)&server_addr,sizeof(server_addr));
/***************HERE WE START**************/
// get the data back
i=recv(s,buf,sizeof(buf),0);
tmit=ntohl((time_t)buf[10]); //# get transmit time
tmit-= 2208988800U;
printf("tmit=%d\n",tmit);
//#compare to system time
printf("Time is time: %s",ctime(&tmit));
char buffer[13];
struct tm * timeinfo;
timeinfo = ctime(&tmit);
strftime (buffer,13,"%04Y%02m%02d%02k%02M",timeinfo);
printf("new buffer:%s\n" ,buffer);
}
是您的代码工作的替换线? – mohit 2013-04-21 18:30:06
它正在工作,但'strftime'是错误的,将错误的数据传递到'char缓冲区[13]' – sven 2013-04-21 18:33:36