len = sr_scpi_read_data(scpi, (char *)devc->buffer, devc->num_samples-devc->num_block_bytes);
if (len == -1) {
sr_err("Read error, aborting capture.");
len = sr_scpi_read_data(scpi, (char *)devc->buffer, devc->num_samples-devc->num_block_bytes);
if (len == -1) {
sr_err("Read error, aborting capture.");