thomasalvatran/read_mbr.c

## read_mbr.c
//Check img whether there is partition in MBR locates at 0x1BE of 1st sector
#include <stdio.h>
#include <stdlib.h>

int main() {
    FILE * in = fopen("test.img", "rb");  //change img to your img
    // FILE * in = fopen("usb.img", "rb");
    unsigned int i, start_sector, length_sectors;

    fseek(in, 0x1BE, SEEK_SET); // go to partition table start

    for(i=0; i<4; i++) { // read all four entries
        printf("Partition entry %d: First byte %02X\n", i, fgetc(in));
        printf("  Partition start in CHS: %02X:%02X:%02X\n", fgetc(in), fgetc(in), fgetc(in));
        printf("  Partition type 0x%02X\n", fgetc(in));
        printf("  Partition end in CHS: %02X:%02X:%02X\n", fgetc(in), fgetc(in), fgetc(in));

        fread(&start_sector, 4, 1, in);
        fread(&length_sectors, 4, 1, in);
        printf("  Relative LBA address 0x%08X, %d sectors long\n", start_sector, length_sectors);
    }

    fclose(in);
    return 0;
}
	//Check img whether there is partition in MBR locates at 0x1BE of 1st sector
	#include <stdio.h>
	#include <stdlib.h>

	int main() {
	FILE * in = fopen("test.img", "rb"); //change img to your img
	// FILE * in = fopen("usb.img", "rb");
	unsigned int i, start_sector, length_sectors;

	fseek(in, 0x1BE, SEEK_SET); // go to partition table start

	for(i=0; i<4; i++) { // read all four entries
	printf("Partition entry %d: First byte %02X\n", i, fgetc(in));
	printf(" Partition start in CHS: %02X:%02X:%02X\n", fgetc(in), fgetc(in), fgetc(in));
	printf(" Partition type 0x%02X\n", fgetc(in));
	printf(" Partition end in CHS: %02X:%02X:%02X\n", fgetc(in), fgetc(in), fgetc(in));

	fread(&start_sector, 4, 1, in);
	fread(&length_sectors, 4, 1, in);
	printf(" Relative LBA address 0x%08X, %d sectors long\n", start_sector, length_sectors);
	}

	fclose(in);
	return 0;
	}