#include <stdio.h>
#include <stdlib.h>
#pragma pack(1)  // Dear GCC:  Don't mess with my data (i.e., by adding
                 //            padding bytes between struct fields).

typedef struct {
    char         floor;
    unsigned int number;
} Room;

int main(int argc, char* argv[]) {
    Room room = { .floor = 'B', .number = 72 };
    printf("{ .floor = '%c', .number = %d }\n", room.floor, room.number);

    const char* filename = "b.binary";
    FILE* fp = fopen(filename, "w");
    if(fp == NULL) {
        fprintf(stderr, "Could not open %s\n", filename);
        return EXIT_FAILURE;
    }

    fwrite(&room, sizeof(room), 1, fp);
    // fwrite(&room, 5, 1, fp);
    //
    // size_t fwrite(const void *ptr, size_t size, size_t nmemb,
    //               FILE *stream);

    fclose(fp);

    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */