The fscanf and fprintf functions
/* The fscanf and fprintf functions
We know how to use scanf() function to take input and printf() function to print the output.
In a similar way, we use the fscanf() function to read data from the file and fprintf() function to write data in the file.
Syntax of fscanf function:
fscanf(fptr, "control string", list_of_var);
Where, fptr is a file pointer. The control string contains the input specification like %d for integer or %c for character. list_of_var is the list of variables.
Syntax of fprintf function:
fprintf(fptr, "control string", list_of_var);
Write a program in C to read and write student name, id and score in a file
We will create a student file for this program.
We will use the fprintf() function to write the data in the file and then using the fscanf() function to read the data from the file.*/
#include <stdio.h>
int main(void) {
// creating a FILE variable
FILE *fptr;
// integer variable
int id, score;
int i, s;
// character variable
char name[255];
char n[255];
// open the file in write mode
fptr = fopen("student", "w");
if (fptr != NULL) {
printf("File created successfully!n");
}
else {
printf("Failed to create the file.n");
// exit status for OS that an error occured
return -1;
}
// get student detail
printf("Enter student name: ");
gets(name);
printf("Enter student ID: ");
scanf("%d", &id);
printf("Enter student score: ");
scanf("%d", &score);
// write data in file
fprintf(fptr, "%d %d %s", id, score, name);
// close connection
fclose(fptr);
// open file for reading
fptr = fopen("student", "r");
// display detail
printf("nStudent Details:n");
fscanf(fptr, "%d %d %[^n]s", &i, &s, n);
printf("ID: %dn", i);
printf("Name: %sn", n);
printf("Score: %dn", s);
printf("nEnd of file.n");
// close connection
fclose(fptr);
return 0;
}