1 files changed, 32 insertions, 0 deletions
diff --git a/pkg/xtools/ranges/rgnext.x b/pkg/xtools/ranges/rgnext.x
new file mode 100644
index 00000000..354ef813
--- /dev/null
+++ b/pkg/xtools/ranges/rgnext.x
@@ -0,0 +1,32 @@
+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include	<mach.h>
+include	<pkg/rg.h>
+
+# RG_NEXT -- Return the next value in a set of ordered and merged ranges.
+# Number is set to the next value in the set of ranges or is unchanged
+# (and EOF is returned) if there are no more values.
+
+int procedure rg_next (rg, number)
+
+pointer	rg			# RANGES pointer
+int	number			# Both input and output parameter
+
+int	next_number, i
+
+begin
+	next_number = number + 1
+
+	do i = 1, RG_NRGS(rg)
+	    if (next_number > RG_X2(rg, i)) {
+		next
+	    } else if (next_number < RG_X1(rg, i)) {
+		number = RG_X1(rg, i)
+	    	return (number)
+	    } else {
+		number = next_number
+		return (number)
+	    }
+
+	return (EOF)
+end