Looping problems socket programming in C

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# 8  
Old 08-08-2011
So ya mean I need to remove the close socket?
I've tried commenting it and found out that it's the read data problem is that true.
I'm not really familiar with the C programming commands so kinda confused with it.
Mind guiding me along?

while (1) /* Loop forever */


        /* Accept a client connection */

        clientFd = accept (serverFd, clientSockAddrPtr, &clientLen);

        //if (fork () == 0) /* Create child to send recipe */





	    printf("You have entered: %s\n",country);

            printf ("%s Capital       : %s\n", country,getCapital(country));

            printf ("%s Currency Code : %s\n", country,getCurrencyCode(country));

            char* capital = getCapital (country);

	    char* currency = getCurrencyCode(country);

            //close (clientFd); /* Close the socket */

           //exit (/* EXIT_SUCCESS */ 0); /* Terminate */



          //close (clientFd); /* Close the client descriptor */



Readdata function

void readData ()


	FILE * pFile;

	NoOfRecordsRead = 0;

   	char buffer [Line_Char_Buffer_Size];

	pFile = fopen (INPUT_FILE_NAME , "r");


	if (pFile == NULL) 

		perror ("Error opening file 'Countries.txt' !");



		while ( !feof (pFile) )


			char* aLine = get_line (buffer, Line_Char_Buffer_Size, pFile);

			if (aLine != NULL)


				globalCountryDataArray [NoOfRecordsRead++] = createCountryRecord (aLine);



     fclose (pFile);




# 9  
Old 08-08-2011
nooo. you do need to loop to accept new connections. maybe something like (untested):

while (1) /* Loop forever */
	/* Accept a client connection */
	clientFd = accept(serverFd, clientSockAddrPtr, &clientLen);

	if (fork () == 0) /* Create child to read */
		memset(country, 0, 300);
		while ((c = read(clientFd, country, 300)) > 0)
			char *capital = getCapital(country);
			char *currency = getCurrencyCode(country);

			printf("You have entered: %s\n",country);
			printf ("%s Capital       : %s\n", country, capital);
			printf ("%s Currency Code : %s\n", country, currency);
		close(clientFd);	/* Close the socket */
		exit(0);		/* Terminate child */
	} else {
		close(clientFd);	/* Close the client descriptor */

This User Gave Thanks to neutronscott For This Post:
# 10  
Old 08-08-2011
It works thanks!! But got a slight problem
The list of output has shown.
I've tried typing the input lets say, Vietnam.
It works for the first time.
The 2nd time I typed Singapore, it works too.
However on the 3rd try, I typed Vietnam again.
It shows Vietnamre which shows that it cannot be found and the re of the previously Singapore is added behind Vietnam.
I've tried entered Netherlands and it works.
When I typed back Vietnam again the letters behind is added with ands.

I've declared the char country to 300 but it' still not working thoughSmilie

Please enter country name > Vietnam
Please enter country name > Singapore
Please enter country name > Vietnam
Please enter country name > Netherlands

You have entered: Vietnam
Vietnam Capital       : Hanoi
Vietnam Currency Code : VND
You have entered: Singapore
Singapore Capital       : Singapore
Singapore Currency Code : SGD
Country 'Vietnamre' not found!
Country 'Vietnamre' not found!
You have entered: Vietnamre
Vietnamre Capital       : (null)
Vietnamre Currency Code : (null)
You have entered: Netherlands
Netherlands Capital       : Amsterdam
Netherlands Currency Code : EUR
You have entered: Vietnamands
Vietnamands Capital       : (null)
Vietnamands Currency Code : (null)

# 11  
Old 08-08-2011
Ah yes of course. You will want the memset() also at the end of that while loop. Or, at beginning you may do country[c]=0 to null terminate it there.

Also while thinking about it, is best to use sizeof(country) in place of the 300 in memset and read. You want to also save 1 byte for NUL termination so in read() replace 300 with "sizeof(country)-1" this is so that if you ever change the size, you only need to change it in 1 place. The rest is taken care of by the compiler.

Last edited by neutronscott; 08-08-2011 at 03:36 AM..
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