Explain End of File (EOF) with a C Program

The End of the File (EOF) indicates the end of input.

After we enter the text, if we press CTRL+Z, the text terminates i.e. it indicates the file reached end nothing to read.

Algorithm

Refer to the algorithm given below for EOF.

Step 1: Open file in write mode.
Step 2: Until character reaches end of the file, write each character in filepointer.
Step 3: Close file.
Step 4: Again open file in read mode.
Step 5: Reading the character from file until fp equals to EOF.
Step 5: Print character on console.
Step 6: Close file.

Example

Following is the C program for End of File (EOF) ?

#include <stdio.h>
int main(){
   char ch;
   FILE *fp;
   fp=fopen("std1.txt","w"); //open the file in write mode
   printf("enter the text then press cntrl Z:
");
   while((ch = getchar())!=EOF) //reading char by char until it equals to EOF{
      i.e. when u press ctrlZ the while loop terminates
      putc(ch,fp);
   }
   fclose(fp);
   fp=fopen("std1.txt","r");
   printf("text on the file:
");
   while ((ch=getc(fp))!=EOF) //reading the character from file until fp equals to EOF{
      putchar(ch);
   }
   fclose(fp);
   return 0;
}

Output

When the above program is executed, it produces the following result ?

enter the text then press cntrl Z:
This is the EOF demonstration example
if your text typing is over press cntrlZ
^Z
text on the file:
This is the EOF demonstration example
if your text typing is over press cntrlZ