C fprintf() fscanf()

The fprintf() and fscanf() are functions used for formatted input and output to and from files, respectively. These functions are similar to printf() and scanf(), which are used for formatted input and output to and from the standard input and output (usually the console).

Here’s a brief overview of fprintf() and fscanf():

1. fprintf() Function:

• The fprintf() function is used to write formatted data to a file.
• It takes three main arguments:
  • A file pointer (FILE*) to the file where you want to write the data.
  • A format string, similar to the format string used in printf(), that specifies the format of the data to be written.
  • Additional arguments corresponding to the format specifiers in the format string.
• Example of fprintf(): #include <stdio.h> int main() { FILE *file = fopen("output.txt", "w"); // Open a file for writing if (file != NULL) { int x = 42; fprintf(file, "The answer is: %d", x); fclose(file); // Close the file } return 0; }

1. fscanf() Function:

• The fscanf() function is used to read formatted data from a file.
• It takes three main arguments:
  • A file pointer (FILE*) to the file from which you want to read the data.
  • A format string, similar to the format string used in scanf(), that specifies the format of the data to be read.
  • Additional arguments (pointers) where the data will be stored based on the format specifiers in the format string.
• Example of fscanf(): #include <stdio.h> int main() { FILE *file = fopen("input.txt", "r"); // Open a file for reading if (file != NULL) { int x; fscanf(file, "The answer is: %d", &x); printf("Read from file: %d\n", x); fclose(file); // Close the file } return 0; }

In both examples, we open a file using fopen(), perform either writing or reading operations using fprintf() or fscanf(), and close the file using fclose() when we’re done. These functions allow you to work with files in a formatted manner, making it easier to read and write structured data.