Write a C program that displays contents of a given file like 'more' utility in Linux

Here, we will write a C program that will display the contents of a file page by page as displayed in Linux using the more command.

This program will show a specific number of lines on the screen first and then wait for the user to hit enter to move to the next page i.e. next set of n lines.

For displaying the content of the file like this we will open the file and print its contents. And maintain a counter for new lines in the file. When this counter reaches n, we will read a key pressed by the user to print further new n lines.

Example

 Live Demo

#include <stdio.h>
void displaytext(char *fname, int n) {
   FILE *fp = fopen(fname, "r");
   int lineCount = 0, ch;
   if (fp == NULL) {
      printf("No such file exists\n");
      return;
   }
   while ((ch = fgetc(fp)) != EOF){
      putchar(ch);
      if (ch == '\n'){
         lineCount++;
         if (lineCount == n){
            lineCount = 0;
            getchar();
         }
      }
   }
   fclose(fp);
}
int main() {
   char fname[] = "main.CPP";
   int n = 10;
   displaytext(fname, n);
   return 0;
}

Output

No such file exists