diff --git a/bfd/unPROTO b/bfd/unPROTO
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+#
+# The PROTO macro is a subterfuge to be compatible with both ANSI and K&R 
+# declaration syntax.  It's not widely known, so for the docn just map the 
+# thing to ANSI declaration syntax.
+# 
+# First, join up defns broken across multiple lines in source---but leave
+# any linebreaks, to prettify our examples 
+:pbegn
+/PROTO(.*, *$/N
+s/\n/?/
+t pbegn
+s/?/\
+/g
+# Now actually do the PROTO interpretation.
+# A PROTO invocation looks like
+#   PROTO( resulttype, function, (arglist));
+s/[ 	]*PROTO(\(.*\),[\n 	]*\(.*\),[\n 	]*\((.*)\));/\1 \2\3;/
+