I wrote this code to send any binary file from server to client (in our example, I am sending sample_file.txt); the client should recreate the file locally. Code works fine (I tested with one or two files). Data is sent in chunks of 256 bytes.
I would appreciate remarks and critique, however, not that much from programming style point of view, rather if there are some major flaws in the networking part/logic or file I/O.
Client:
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <arpa/inet.h>
int main(void)
{
int sockfd = 0;
int bytesReceived = 0;
char recvBuff[256];
memset(recvBuff, '0', sizeof(recvBuff));
struct sockaddr_in serv_addr;
/* Create a socket first */
if((sockfd = socket(AF_INET, SOCK_STREAM, 0))< 0)
{
printf("\n Error : Could not create socket \n");
return 1;
}
/* Initialize sockaddr_in data structure */
serv_addr.sin_family = AF_INET;
serv_addr.sin_port = htons(5000); // port
serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
/* Attempt a connection */
if(connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr))<0)
{
printf("\n Error : Connect Failed \n");
return 1;
}
/* Create file where data will be stored */
FILE *fp;
fp = fopen("sample_file.txt", "ab");
if(NULL == fp)
{
printf("Error opening file");
return 1;
}
/* Receive data in chunks of 256 bytes */
while((bytesReceived = read(sockfd, recvBuff, 256)) > 0)
{
printf("Bytes received %d\n",bytesReceived);
// recvBuff[n] = 0;
fwrite(recvBuff, 1,bytesReceived,fp);
// printf("%s \n", recvBuff);
}
if(bytesReceived < 0)
{
printf("\n Read Error \n");
}
return 0;
}
Server:
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
int main(void)
{
int listenfd = 0;
int connfd = 0;
struct sockaddr_in serv_addr;
char sendBuff[1025];
int numrv;
listenfd = socket(AF_INET, SOCK_STREAM, 0);
printf("Socket retrieve success\n");
memset(&serv_addr, '0', sizeof(serv_addr));
memset(sendBuff, '0', sizeof(sendBuff));
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
serv_addr.sin_port = htons(5000);
bind(listenfd, (struct sockaddr*)&serv_addr,sizeof(serv_addr));
if(listen(listenfd, 10) == -1)
{
printf("Failed to listen\n");
return -1;
}
while(1)
{
connfd = accept(listenfd, (struct sockaddr*)NULL ,NULL);
/* Open the file that we wish to transfer */
FILE *fp = fopen("sample_file.txt","rb");
if(fp==NULL)
{
printf("File opern error");
return 1;
}
/* Read data from file and send it */
while(1)
{
/* First read file in chunks of 256 bytes */
unsigned char buff[256]={0};
int nread = fread(buff,1,256,fp);
printf("Bytes read %d \n", nread);
/* If read was success, send data. */
if(nread > 0)
{
printf("Sending \n");
write(connfd, buff, nread);
}
/*
* There is something tricky going on with read ..
* Either there was error, or we reached end of file.
*/
if (nread < 256)
{
if (feof(fp))
printf("End of file\n");
if (ferror(fp))
printf("Error reading\n");
break;
}
}
close(connfd);
sleep(1);
}
return 0;
}
