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git-svn-id: svn://svn.valgrind.org/valgrind/trunk@3902 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/coregrind/pub_core_libcproc.h b/coregrind/pub_core_libcproc.h
index 2079ed5..486bebf 100644
--- a/coregrind/pub_core_libcproc.h
+++ b/coregrind/pub_core_libcproc.h
@@ -38,7 +38,8 @@
 
 #include "pub_tool_libcproc.h"
 
-/* The directory we look for all our auxillary files in */
+/* The directory we look for all our auxillary files in.  Useful for
+   running Valgrind out of a build tree without having to do "make install". */
 #define VALGRINDLIB	"VALGRINDLIB"
 
 /* Additional command-line arguments; they are overridden by actual