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diff --git a/test/bctest b/test/bctest
index 23651524398e0cd936922799577827417571f28f..38e43efecc2a816b79f81451f138dc39e62d263e 100755 (executable)
--- a/test/bctest
+++ b/test/bctest
@@ -1,5 +1,10 @@
 #!/bin/sh
 
+# This script is used by test/Makefile.ssl to check whether a sane 'bc'
+# is installed.
+# ('make test_bn' should not try to run 'bc' if it does not exist or if
+# it is the broken SunOS 5.[78] bc, which fails the following test.)
+
 if [ 0 != "`bc <<\EOF
 obase=16
 ibase=16