How can I check the backup size?

You can check the size of a backup file using a simple C program. Here's an example that opens a backup file and retrieves its size:

#include <stdio.h>
#include <stdlib.h>

int main() {
    FILE *fp;
    int size = 0;

    // Replace "backup_file.bak" with your backup file name
    fp = fopen("backup_file.bak", "r");

    if (fp == NULL) {
        printf("\nFile unable to open...\n");
        return 1;
    } else {
        printf("\nFile opened...\n");
    }

    fseek(fp, 0, 2); // Move to the end of the file
    size = ftell(fp); // Get the current position (size of the file)

    printf("The size of the backup file is: %d bytes\n", size);

    fclose(fp);
    return 0;
}

Make sure to replace "backup_file.bak" with the actual name of your backup file. This program will print the size of the specified backup file in bytes.