UART on DE2

This is my code:

# include <stdio.h>

# include <string.h>

int main ()

{

char* msg = "Detected the character 't'.\n";

FILE* fp;

char prompt = 0;

fp = fopen ("/dev/rs232", "r+"); //Open file for reading and writing

if (fp)

{

while (prompt != 'v')

{ // Loop until we receive a 'v'.

fprintf(fp, "Entered while.\n");

prompt = getc(fp); // Get a character from the UART.

if (prompt == 't')

{ // Print a message if character is 't'.

fwrite (msg, strlen (msg), 1, fp);

}

}

fprintf(fp, "Closing the UART file.\n");

fclose (fp);

}

return 0;

}

I have made some changes after I wrote the post and now I'm able to send and receive characters. Although, it isn't suitable for my application to use polling to receive characters, so I need to implement interrupt at least for reception, but I have no idea how to do this. Any tip?