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

int main(int argc, char* argv[]) {
    char const* filename = __FILE__ ".bin"; // "write_doubles.c.bin"
    // file opened in wrtie mode
    // no indicator here its a binary file
    FILE* file = fopen(filename, "w");

    // writing
    double numbers[] = { 1234.0, 6.0, 12.78, -127.125, 1 };
    // this trick ONLY works for arrays, not addresses
    int length = sizeof(numbers) / sizeof(numbers[0]);
    fwrite(numbers, sizeof(numbers[0]), length, file);

    // don't forget to close
    fclose(file);

    return EXIT_SUCCESS;
}
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