tcpc.c

Linux下的C编程

#include <stdio.h> 
#include <stdlib.h> 
#include <errno.h> 
#include <string.h> 
#include <netdb.h> 
#include <sys/types.h> 
#include <netinet/in.h> 
#include <sys/socket.h> 
#include <sys/stat.h>

#ifndef false
	#define false	0
#endif

#ifndef true
	#define true	1
#endif
typedef int	bool;
int main(int argc, char *argv[]) 
{ 
	int i=0;
    	int sockfd, numbytes;  
	char datafile[256];
	struct stat st;
	bool isExist = false;
	int size;
	int length;
	char file_buffer[4096];
	int ai_number,di_number;
    	struct hostent *he; 
    	struct sockaddr_in their_addr; 
    	int myport; 

    	char *home = getenv("CEMS");
	char config[256];
	strcpy(config,home);
	printf("1config is %s\n",config);
	strcat(config,"/src/TCPrt/tcpc.ini");
	printf("2config is %s\n",config);
	char ip[20],rtpath[256];
	int cycle=10;
	strcpy(rtpath,home);
	strcat(rtpath,"/data");
	printf("rtpath is %s\n",rtpath);
	FILE *fpini;
	char buffport[20],buffcycle[10];
	if((fpini=fopen(config,"r"))!=NULL)
	{
		fscanf(fpini,"%s\n",ip);
		printf("ip is %s\n",ip);
		fscanf(fpini,"%s\n",buffport);
		myport=atoi(buffport);
		printf("myport is %d\n",myport);
		//fscanf(fpini,"%s",buffcycle);
		//cycle==atoi(buffcycle);
		printf("cycle is %d\n",cycle);
		fclose(fpini);
	}
	
	fflush(stdout);
	if((he=gethostbyname(ip))==NULL) 
	{ 
        	herror("gethostbyname"); 
        	exit(1); 
	}
	FILE *fp;
	i=0;
	while(1)
	{
		if ((sockfd = socket(PF_INET, SOCK_STREAM, 0)) == -1) 
		{ 
        		printf("socket error!\n"); 
			fflush(stdout);
			//exit(1);
        		sleep(cycle);
        		continue; 
    		} 
    		their_addr.sin_family=PF_INET; 
    		their_addr.sin_port=htons(myport); 
    		their_addr.sin_addr = *((struct in_addr *)he->h_addr); 
    		bzero(&(their_addr.sin_zero),0); 
    		if (connect(sockfd, (struct sockaddr *)&their_addr, sizeof(struct sockaddr)) == -1)
		{ 
        		//perror("connect"); 
        		printf("connetct failed!");
			fflush(stdout);
        		sleep(cycle);
        		//exit(1); 
        		continue;
    		} 
		printf("ok!");
			//prepare send data buffer
		i++;
			isExist = false;
			sprintf(datafile,"%s/realtime%d.txt",rtpath,i);
			printf("datafile is %s\n",datafile);
			fflush(stdout);
			if(stat(datafile,&st)==0) 
			{ //file exist.
				isExist = true;
				size = st.st_size;
			}
			else
			{
				if(i>4)
				{
					i=0;
				}
				sleep(cycle);
				continue;
			}
			bzero(&st,sizeof(struct stat));	
			if(isExist)
			{
				bzero(file_buffer,4096);
				//according save format to load data.
				FILE *fp;
				if((fp=fopen(datafile,"rb"))!=NULL){
					fread(file_buffer,size,1,fp);
					fclose(fp);
				}
				char PacketType[5];
				memcpy(PacketType,file_buffer,4);
        			PacketType[4]=0;
				printf("PacketType is %s\n",PacketType);
				fflush(stdout);
				if(strcmp(PacketType,"REAL")!=0){
					printf("REAL is error \n");
					fflush(stdout);
					break;
				}
				memcpy(&ai_number,file_buffer+20,4);
				memcpy(&di_number,file_buffer+24,4);
				length = 30 + ai_number*4 + di_number*1;
				printf("length is %d\n",length);
				fflush(stdout);
			}
	    		if(write(sockfd,file_buffer,length)==-1) 
   			{ 
         			fprintf(stderr,"Write Error:%s\n",strerror(errno)); 
         			exit(1); 
    			}
    			printf("write finished!\n"); 
   			/*if ((numbytes=recv(sockfd, buf, MAXDATASIZE, 0)) == -1) { 
        			perror("recv"); 
        			exit(1); 
    			} 
    			printf("Received: %s\n",buf); */
    		close(sockfd); 
		if(i>=4)
		{
			sleep(cycle);
			i=0;
		}
		else
		{
			sleep(1);
		}
		printf("xxx!\n"); 
	}
    	return 0; 
}