daytimetcpcli.c

这是一个linux下时间通信的server端和client端的源码,下载后分别保存

/* daytimetcpcli.c */
#define MAXLINE 4096
#define LISTENQ 1024
#define SA struct sockaddr

#include "curses.h"
#include "stdlib.h"
#include "stdio.h"
#include "errno.h"
#include "netdb.h"
#include "string.h"
#include "sys/time.h"
#include "sys/types.h"
#include "sys/socket.h"
#include "netinet/in.h"
#include "memory.h"
#include "stdarg.h"
#include "syslog.h"
int daemon_proc;

static void err_doit(int errnoflag,int level,const char * fmt,va_list ap)
{
	int errno_save,n;
	char buf[MAXLINE];
	errno_save = errno;
#ifdef HAVE_VSNPRINTF
	vsnprlntf(buf,sizeof(buf),fmt,ap);
#else
	vsprintf(buf,fmt,ap);
#endif
	n = strlen(buf);
	if(errnoflag)
		snprintf(buf + n,sizeof(buf) -n,":%s",strerror(errno_save));
	strcat(buf,"\n");
	if(daemon_proc){
		syslog(level,buf);
	}else{
		fflush(stdout);
		fputs(buf,stderr);
		fflush(stderr);
	}
	return;
}
err_sys(const char * fmt,...)
{
	va_list ap;
	va_start(ap,fmt);
	err_doit(1,LOG_ERR,fmt,ap);
	va_end(ap);
	exit(1);
}
err_quit(const char * fmt,...)
{
	va_list ap;
	va_start(ap,fmt);
	err_doit(0,LOG_ERR,fmt,ap);
	va_end(ap);
	exit(1);
}
/* Define bzero() as a macro if it's not in standard C library. */
#ifndef HAVE_BRZEO 
#define bzero(ptr,n) memset(ptr,0,n) 
#endif

int main(int argc,char * * argv)
{
	int sockfd,n;
	struct sockaddr_in servaddr;
	char recvline[MAXLINE+1];
	if(argc != 2)
		err_quit("usage:a.out<IPaggress>");
	if((sockfd = socket(AF_INET,SOCK_STREAM,0))<0)
		err_sys("socket error");
	bzero(&servaddr,sizeof(servaddr));
	servaddr.sin_family = AF_INET;
        //servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
	servaddr.sin_port = htons(13);
	if(inet_pton(AF_INET,argv[1],&servaddr.sin_addr) <= 0)
		err_quit("inet_pton error for %s",argv[1]);
	if(connect(sockfd,(SA *)&servaddr,sizeof(servaddr)) < 0)
		err_sys("connect error");
	while((n = read(sockfd,recvline,MAXLINE))  > 0){
		recvline[n] = 0;
		if(fputs(recvline,stdout) == EOF)
			err_sys("fputs error");
	}
	if(n < 0)
		err_sys("read error");
	exit(0);
}