help me with this memory mapped file code

[chinu]

hello everybody,

I am new to this forum..I am trying to run a code..
I created a text file first with the name mmap.txt and wrote some lines in that....but I dont know why its not working...I just used simple printf() scanf() functions.... It reads integer value for the position three times...but doesnt reads a character....can somebody please help me with that?
the code is:

#include<unistd.h>
#include<sys/mman.h>
#include<sys/types.h>
#include<fcntl.h>
#include<stdio.h>
#include<string.h>

int main()
{
   int fd; 
   char *fileptr; 
   int i;
   int x;
   char ch;
   fd=open("mmap.txt",O_RDWR);
   fileptr=mmap(0,26,PROT_READ | PROT_WRITE,MAP_SHARED,fd,0);
   for(i=0;i<3;i++)
   {
      printf("Enter the position in the file you want to change: ");
      scanf("%d",&x);
      printf("\n");
      printf("Enter the new letter for that position: ");
      scanf("%c",&ch);
      printf("\n");
      fileptr[x-1]=ch;
      printf("\n");
   }
  munmap(fileptr,26);
  close(fd);
  return 1;
  }

[Salem]

You type in
42\n

scanf %d will read the 42
scanf %c will read the \n

An easy fix would be to use %s with a char array, then use the first character.

[chinu]

Thanks a lot Salem!!! thats working now.I appreciate your help.....