Function esp_idf_sys::esp_http_client_read

pub unsafe extern "C" fn esp_http_client_read(
    client: esp_http_client_handle_t,
    buffer: *mut c_char,
    len: c_int
) -> c_int

@brief Read data from http stream

@param[in] client The esp_http_client handle @param buffer The buffer @param[in] len The length

@return - (-1) if any errors - Length of data was read

@note (-ESP_ERR_HTTP_EAGAIN = -0x7007) is returned when call is timed-out before any data was ready