1 files changed, 24 insertions, 0 deletions
diff --git a/sys/osb/achtbd.c b/sys/osb/achtbd.c
new file mode 100644
index 00000000..deb2f23a
--- /dev/null
+++ b/sys/osb/achtbd.c
@@ -0,0 +1,24 @@
+/* Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+ */
+
+#define	import_spp
+#define import_knames
+#include <iraf.h>
+
+/* ACHTB_ -- Unpack an unsigned byte array into an SPP array.
+ * The loop runs in the reverse direction so that the unpack can be
+ * performed in place (a and b can be the same array).
+ */
+void
+ACHTBD (
+  XCHAR		*a,
+  XDOUBLE	*b,
+  XINT		*npix
+)
+{
+	register XUBYTE	*ip, *first = (XUBYTE *)a;
+	register XDOUBLE	*op;
+
+	for (ip = &first[*npix], op = &((XDOUBLE *)b)[*npix];  ip > first;  )
+		*--op = *--ip;
+}