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C read file program

C read file program: This C language program reads a file whose name is entered by a user and displays its contents on the screen. Function fopen is used to open a file; it returns a pointer to structure FILE which is a predefined structure in "stdio.h" header file. If the file is successfully opened then fopen returns a pointer to the file and if it is unable to open the file then it returns NULL. Function fgetc returns a character which is read from the file, and fclose function closes the file. Opening a file means we bring the file contents from disk to RAM to perform operations on it. The file to be opened must be present in the directory in which the executable file of this program is present.

File reading program in C

C programming code to open a file and print its contents on screen.

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
   char ch, file_name[25];
   FILE *fp;
 
   printf("Enter the name of file you wish to see\n");
   gets(file_name);
 
   fp = fopen(file_name,"r"); // read mode
 
   if( fp == NULL )
   {
      perror("Error while opening the file.\n");
      exit(EXIT_FAILURE);
   }
 
   printf("The contents of %s file are :\n", file_name);
 
   while( ( ch = fgetc(fp) ) != EOF )
      printf("%c",ch);
 
   fclose(fp);
   return 0;
}

Download Read file program.

Read file C program output:
C read file program output

There are blank lines present at the end of the file. In our program we have opened only one file, you can open multiple files in a single program and different modes as required. File handling is essential when we wish to store data permanently on a storage device. All variables and data of a program are lost when it exit if that data is required later we need to store it in a file.