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diff --git a/sys/gio/ncarutil/sysint/gbytes.x b/sys/gio/ncarutil/sysint/gbytes.x
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+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+# GBYTES -- Locally implemented bit unpacker for the NCAR extended metacode
+# translator.   3 may 84 cliff stoll
+# Required for the ncar/gks vdi metacode generator.
+#
+# Essentially this routine accepts an array which is a packed series of bits. 
+# [array BUFIN], and unpacks them into an array [array BUFOUT].  Received
+# integer INDEX is the beginning bit in BUFIN  where information is to be 
+# placed.  INDEX is zero indexed.  Received integer argument SIZE is the 
+# number of bits in each "information packet".  Received argument SKIP is the 
+# number of bits to skip between bit packets.  For more info, see page 4 of 
+# the NCAR "Implementaton details for the new metafile translator, version 1.0"
+
+procedure gbytes (bufin, bufout, index, size, skip, count)
+
+int	bufout[ARB], bufin[ARB], index, size, skip, count
+int	pack
+int	offset
+int	bitupk()	# Iraf function to unpack bits
+
+begin
+	for (pack = 1; pack <= count ; pack = pack+1) {
+	    # Offset is a bit offset into the input buffer bufin.
+	    # (offset is 1- indexed; INDEX is zero indexed)
+
+	    offset = (size + skip) * (pack - 1) + index + 1
+	    bufout(pack) = bitupk(bufin, offset, size)
+	}
+end