Add more info about compiling docs.

diff --git a/Documentation/user/install.itely b/Documentation/user/install.itely
index ef7e4ffaa28c41a62d1a9f1e463807b3409ec997..0e62f977f68b6d4e182ceacd5449b982580c2434 100644 (file)
--- a/Documentation/user/install.itely
+++ b/Documentation/user/install.itely
@@ -279,6 +279,23 @@ unstable Lily will fail to build the docs.
 You may build the manual ( Documentation/user/ ) without building all
 the input/* stuff.
 
+@refbugs
+
+You may also need to create a script for @command{pngtopnm} and
+@code{pnmtopng}.  On Linux, I use this:
+
+@verbatim
+export LD_LIBRARY_PATH=/usr/lib
+exec /usr/bin/pngtopnm "$@"
+@end verbatim
+
+On OSX, I use this:
+
+@verbatim
+export DYLD_LIBRARY_PATH=/sw/lib
+exec /sw/bin/pngtopnm "$@" 
+@end verbatim
+
 
 @node Testing LilyPond
 @subsection Testing LilyPond