Function array_fromfile_binary

numpy/core/src/multiarray/ctors.c:3306–3355

This array creation function does not steal the reference to dtype. */

/* This array creation function does not steal the reference to dtype. */
static PyArrayObject *
array_fromfile_binary(FILE *fp, PyArray_Descr *dtype, npy_intp num, size_t *nread)
{
    PyArrayObject *r;
    npy_off_t start, numbytes;
    int elsize;

    if (num < 0) {
        int fail = 0;
        start = npy_ftell(fp);
        if (start < 0) {
            fail = 1;
        }
        if (npy_fseek(fp, 0, SEEK_END) < 0) {
            fail = 1;
        }
        numbytes = npy_ftell(fp);
        if (numbytes < 0) {
            fail = 1;
        }
        numbytes -= start;
        if (npy_fseek(fp, start, SEEK_SET) < 0) {
            fail = 1;
        }
        if (fail) {
            PyErr_SetString(PyExc_OSError,
                            "could not seek in file");
            return NULL;
        }
        num = numbytes / dtype->elsize;
    }

    /*
     * Array creation may move sub-array dimensions from the dtype to array
     * dimensions, so we need to use the original element size when reading.
     */
    elsize = dtype->elsize;

    Py_INCREF(dtype);  /* do not steal the original dtype. */
    r = (PyArrayObject *)PyArray_NewFromDescr(&PyArray_Type, dtype, 1, &num,
                                              NULL, NULL, 0, NULL);
    if (r == NULL) {
        return NULL;
    }

    NPY_BEGIN_ALLOW_THREADS;
    *nread = fread(PyArray_DATA(r), elsize, num, fp);
    NPY_END_ALLOW_THREADS;
    return r;
}

/*
 * Create an array by reading from the given stream, using the passed