--- a/ater/read_file.c	Tue Sep 24 06:15:40 2024 +0000
+++ b/ater/read_file.c	Wed Sep 25 05:53:38 2024 +0000
@@ -96,3 +96,68 @@
 	*size_ret = nframes;
 	return 0;
 }
+
+static int check_magic_d144(const uint8_t *buf, unsigned nframes)
+{
+	unsigned n;
+
+	for (n = 0; n < nframes; n++) {
+		if (*buf != 0xD4)
+			return -1;
+		buf += 38;
+	}
+	return 0;
+}
+
+int read_binary_file_d144(const char *filename, uint8_t **bufret,
+			  unsigned *size_ret)
+{
+	int fd, rc;
+	struct stat st;
+	uint8_t *buf;
+	unsigned nframes;
+
+	fd = open(filename, O_RDONLY);
+	if (fd < 0) {
+		perror(filename);
+		return -1;
+	}
+	fstat(fd, &st);
+	if (!S_ISREG(st.st_mode)) {
+		close(fd);
+		fprintf(stderr, "error: %s is not a regular file\n", filename);
+		return -1;
+	}
+	if (!st.st_size) {
+		close(fd);
+		fprintf(stderr, "error: %s is an empty file\n", filename);
+		return -1;
+	}
+	if (st.st_size % 38) {
+		close(fd);
+		fprintf(stderr,
+			"error: size of %s is not a multiple of 38 bytes\n",
+			filename);
+		return -1;
+	}
+	buf = malloc(st.st_size);
+	if (!buf) {
+		close(fd);
+		fprintf(stderr, "unable to malloc buffer for %s\n", filename);
+		return -1;
+	}
+	read(fd, buf, st.st_size);
+	close(fd);
+	nframes = st.st_size / 38;
+
+	rc = check_magic_d144(buf, nframes);
+	if (rc < 0) {
+		free(buf);
+		fprintf(stderr, "error: %s is not a valid D144 test file\n",
+			filename);
+		return -1;
+	}
+	*bufret = buf;
+	*size_ret = nframes;
+	return 0;
+}