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diff --git a/sys/qpoe/qpexgetat.x b/sys/qpoe/qpexgetat.x
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+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include	<mach.h>
+include	"qpex.h"
+
+# QPEX_GETATTRIBUTE -- Get the filter expression for the named attribute
+# as a text string.  The length of the string is returned as the function
+# value.  If the referenced QPEX descriptor does not contain any filter
+# terms for the named attribute, zero will be returned.  If the expression
+# contains multiple eterms the successive terms will be delimited by
+# semicolons, e.g., "(a:b,c:d); (e:f,g)".  The lists of ranges within an
+# eterm are OR-ed to produce a filter term; successive eterms are AND-ed
+# to produce the final filter (hence the example above is equivalent to
+# "(a to b OR c to d) AND (e to f OR g)").
+
+int procedure qpex_getattribute (ex, attribute, outstr, maxch)
+
+pointer	ex			#I QPEX descriptor
+char	attribute[ARB]		#I attribute name
+char	outstr[maxch]		#O receives the filter string
+int	maxch			#I max chars out
+
+pointer	sp, atname, et
+int	nchars, op, otop
+int	gstrcpy(), qp_expandtext()
+bool	strne()
+
+begin
+	call smark (sp)
+	call salloc (atname, SZ_FNAME, TY_CHAR)
+
+	# Translate attribute name, in case it is aliased.
+	nchars = qp_expandtext (EX_QP(ex), attribute, Memc[atname], SZ_FNAME)
+
+	# Construct filter expression for named attribute.
+	op = 1
+	otop = maxch + 1
+	for (et=EX_ETHEAD(ex);  et != NULL;  et=ET_NEXT(et)) {
+	    if (ET_DELETED(et) == YES)
+		next
+
+	    # Skip entry if not for the named attribute.
+	    if (strne (Memc[ET_ATNAME(et)], Memc[atname]))
+		next
+
+	    # Add term delimiter if not first term.
+	    if (op > 1) {
+		outstr[op] = ';';  op = min(otop, op + 1)
+		outstr[op] = ' ';  op = min(otop, op + 1)
+	    }
+
+	    # The expression text (may be very large).
+	    op = min (otop,
+		op + gstrcpy (Memc[ET_EXPRTEXT(et)], outstr[op], otop-op))
+	}
+	outstr[op] = EOS
+
+	# Return the string length, or zero if no filter for named attribute.
+	call sfree (sp)
+	return (op - 1)
+end