[svn-r606] Debugging can be enabled/disabled at runtime though code is still

conditionally included at compile time.  Tracing and debugging share
the same environment variable.  All is documented in Debugging.html.

19 files changed, 765 insertions, 582 deletions

diff --git a/src/.distdep b/src/.distdep
index 9f9d5a9..e5d6c0d 100644
--- a/src/.distdep
+++ b/src/.distdep
@@ -1,34 +1,3 @@
-H5.o: \
-   H5.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5ACprivate.h \
-   H5ACpublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Ipublic.h \
-   H5Dpublic.h \
-   H5Bprivate.h \
-   H5Bpublic.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5Iprivate.h \
-   H5MMprivate.h \
-   H5MMpublic.h \
-   H5Pprivate.h \
-   H5Ppublic.h \
-   H5Zpublic.h \
-   H5Sprivate.h \
-   H5Spublic.h \
-   H5Gprivate.h \
-   H5Gpublic.h \
-   H5Oprivate.h \
-   H5Opublic.h \
-   H5HGprivate.h \
-   H5HGpublic.h \
-   H5Tprivate.h \
-   H5Tpublic.h
 H5A.o: \
    H5A.c \
    H5private.h \
@@ -62,111 +31,6 @@ H5A.o: \
    H5Ppublic.h \
    H5Apkg.h \
    H5Aprivate.h
-H5AC.o: \
-   H5AC.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5ACprivate.h \
-   H5ACpublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Ipublic.h \
-   H5Dpublic.h \
-   H5Eprivate.h \
-   H5Epublic.h
-H5B.o: \
-   H5B.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5ACprivate.h \
-   H5ACpublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Ipublic.h \
-   H5Dpublic.h \
-   H5Bprivate.h \
-   H5Bpublic.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5MFprivate.h \
-   H5MFpublic.h \
-   H5MMprivate.h
-H5D.o: \
-   H5D.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5Iprivate.h \
-   H5Ipublic.h \
-   H5ACprivate.h \
-   H5ACpublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Dpublic.h \
-   H5Dprivate.h \
-   H5Gprivate.h \
-   H5Gpublic.h \
-   H5Bprivate.h \
-   H5Bpublic.h \
-   H5Oprivate.h \
-   H5Opublic.h \
-   H5HGprivate.h \
-   H5HGpublic.h \
-   H5Tprivate.h \
-   H5Tpublic.h \
-   H5Sprivate.h \
-   H5Spublic.h \
-   H5Zprivate.h \
-   H5Zpublic.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5HLprivate.h \
-   H5HLpublic.h \
-   H5MFprivate.h \
-   H5MFpublic.h
-H5E.o: \
-   H5E.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5Iprivate.h \
-   H5Ipublic.h \
-   H5Eprivate.h
-H5F.o: \
-   H5F.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5Aprivate.h \
-   H5Apublic.h \
-   H5Ipublic.h \
-   H5Gprivate.h \
-   H5Gpublic.h \
-   H5Bprivate.h \
-   H5Bpublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Dpublic.h \
-   H5Dprivate.h \
-   H5Oprivate.h \
-   H5Opublic.h \
-   H5HGprivate.h \
-   H5HGpublic.h \
-   H5Tprivate.h \
-   H5Tpublic.h \
-   H5Sprivate.h \
-   H5Spublic.h \
-   H5Zprivate.h \
-   H5Zpublic.h \
-   H5Iprivate.h \
-   H5ACprivate.h \
-   H5ACpublic.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5MMprivate.h \
-   H5MMpublic.h
 H5Farray.o: \
    H5Farray.c \
    H5private.h \
@@ -203,55 +67,6 @@ H5Fcore.o: \
    H5Eprivate.h \
    H5Epublic.h \
    H5Ipublic.h
-H5Ffamily.o: \
-   H5Ffamily.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5Ipublic.h
-H5Fistore.o: \
-   H5Fistore.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5Dprivate.h \
-   H5Dpublic.h \
-   H5Ipublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Gprivate.h \
-   H5Gpublic.h \
-   H5Bprivate.h \
-   H5Bpublic.h \
-   H5Oprivate.h \
-   H5Opublic.h \
-   H5HGprivate.h \
-   H5HGpublic.h \
-   H5Tprivate.h \
-   H5Tpublic.h \
-   H5Sprivate.h \
-   H5Spublic.h \
-   H5Zprivate.h \
-   H5Zpublic.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5MFprivate.h \
-   H5MFpublic.h
-H5Flow.o: \
-   H5Flow.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5Ipublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Dpublic.h \
-   H5MMprivate.h \
-   H5MMpublic.h
 H5Fmpio.o: \
    H5Fmpio.c \
    H5private.h \
@@ -450,24 +265,6 @@ H5HG.o: \
    H5MFprivate.h \
    H5MFpublic.h \
    H5MMprivate.h
-H5HL.o: \
-   H5HL.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5ACprivate.h \
-   H5ACpublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Ipublic.h \
-   H5Dpublic.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5HLprivate.h \
-   H5HLpublic.h \
-   H5MFprivate.h \
-   H5MFpublic.h \
-   H5MMprivate.h
 H5I.o: \
    H5I.c \
    H5private.h \
@@ -476,14 +273,6 @@ H5I.o: \
    H5Iprivate.h \
    H5Ipublic.h \
    H5Eprivate.h
-H5MF.o: \
-   H5MF.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5Ipublic.h
 H5MM.o: \
    H5MM.c \
    H5private.h \
@@ -492,34 +281,6 @@ H5MM.o: \
    H5Eprivate.h \
    H5Epublic.h \
    H5Ipublic.h
-H5O.o: \
-   H5O.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5ACprivate.h \
-   H5ACpublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Ipublic.h \
-   H5Dpublic.h \
-   H5Eprivate.h \
-   H5Epublic.h \
-   H5MFprivate.h \
-   H5MFpublic.h \
-   H5MMprivate.h \
-   H5MMpublic.h \
-   H5Oprivate.h \
-   H5Opublic.h \
-   H5Gprivate.h \
-   H5Gpublic.h \
-   H5Bprivate.h \
-   H5Bpublic.h \
-   H5HGprivate.h \
-   H5HGpublic.h \
-   H5Tprivate.h \
-   H5Tpublic.h \
-   H5Sprivate.h
 H5Oattr.o: \
    H5Oattr.c \
    H5private.h \
@@ -829,31 +590,31 @@ H5P.o: \
    H5Eprivate.h \
    H5Epublic.h \
    H5MMprivate.h
-H5S.o: \
-   H5S.c \
+H5Sall.o: \
+   H5Sall.c \
    H5private.h \
    H5public.h \
    H5config.h \
-   H5Iprivate.h \
-   H5Ipublic.h \
    H5Eprivate.h \
    H5Epublic.h \
-   H5MMprivate.h \
-   H5MMpublic.h \
-   H5Oprivate.h \
-   H5Opublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Dpublic.h \
+   H5Ipublic.h \
+   H5Sprivate.h \
+   H5Spublic.h \
    H5Gprivate.h \
    H5Gpublic.h \
    H5Bprivate.h \
    H5Bpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Dpublic.h \
+   H5Oprivate.h \
+   H5Opublic.h \
    H5HGprivate.h \
    H5HGpublic.h \
-   H5Tprivate.h
-H5Sall.o: \
-   H5Sall.c \
+   H5Tprivate.h \
+   H5Tpublic.h
+H5Shyper.o: \
+   H5Shyper.c \
    H5private.h \
    H5public.h \
    H5config.h \
@@ -875,14 +636,16 @@ H5Sall.o: \
    H5HGpublic.h \
    H5Tprivate.h \
    H5Tpublic.h
-H5Shyper.o: \
-   H5Shyper.c \
+H5Spoint.o: \
+   H5Spoint.c \
    H5private.h \
    H5public.h \
    H5config.h \
    H5Eprivate.h \
    H5Epublic.h \
    H5Ipublic.h \
+   H5MMprivate.h \
+   H5MMpublic.h \
    H5Sprivate.h \
    H5Spublic.h \
    H5Gprivate.h \
@@ -895,17 +658,18 @@ H5Shyper.o: \
    H5Oprivate.h \
    H5Opublic.h \
    H5HGprivate.h \
-   H5HGpublic.h \
-   H5Tprivate.h \
-   H5Tpublic.h
-H5Smpio.o: \
-   H5Smpio.c \
+   H5HGpublic.h
+H5Sselect.o: \
+   H5Sselect.c \
    H5private.h \
    H5public.h \
    H5config.h \
    H5Eprivate.h \
    H5Epublic.h \
    H5Ipublic.h \
+   H5Iprivate.h \
+   H5MMprivate.h \
+   H5MMpublic.h \
    H5Sprivate.h \
    H5Spublic.h \
    H5Gprivate.h \
@@ -920,60 +684,245 @@ H5Smpio.o: \
    H5HGprivate.h \
    H5HGpublic.h \
    H5Tprivate.h \
-   H5Tpublic.h
-H5Spoint.o: \
-   H5Spoint.c \
+   H5Tpublic.h \
+   H5Zprivate.h \
+   H5Zpublic.h
+H5Tbit.o: \
+   H5Tbit.c \
    H5private.h \
    H5public.h \
    H5config.h \
    H5Eprivate.h \
    H5Epublic.h \
    H5Ipublic.h \
+   H5Iprivate.h \
+   H5Tpkg.h \
+   H5HGprivate.h \
+   H5HGpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Dpublic.h \
+   H5Tprivate.h \
+   H5Tpublic.h \
+   H5Gprivate.h
+H5Tconv.o: \
+   H5Tconv.c \
+   H5Iprivate.h \
+   H5Ipublic.h \
+   H5public.h \
+   H5config.h \
+   H5private.h \
+   H5Eprivate.h \
+   H5Epublic.h \
    H5MMprivate.h \
    H5MMpublic.h \
-   H5Sprivate.h \
-   H5Spublic.h \
+   H5Tpkg.h \
+   H5HGprivate.h \
+   H5HGpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Dpublic.h \
+   H5Tprivate.h \
+   H5Tpublic.h \
    H5Gprivate.h \
    H5Gpublic.h \
    H5Bprivate.h \
-   H5Bpublic.h \
+   H5Bpublic.h
+H5Tinit.o: \
+   H5Tinit.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5Iprivate.h \
+   H5Ipublic.h \
+   H5Eprivate.h \
+   H5Epublic.h \
+   H5MMprivate.h \
+   H5MMpublic.h \
+   H5Tpkg.h \
+   H5HGprivate.h \
+   H5HGpublic.h \
    H5Fprivate.h \
    H5Fpublic.h \
    H5Dpublic.h \
+   H5Tprivate.h
+H5TB.o: \
+   H5TB.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5Iprivate.h \
+   H5Ipublic.h \
+   H5Eprivate.h
+H5V.o: \
+   H5V.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5Eprivate.h \
+   H5Epublic.h \
+   H5Ipublic.h \
    H5Oprivate.h \
    H5Opublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Dpublic.h \
+   H5Gprivate.h \
+   H5Gpublic.h \
+   H5Bprivate.h \
+   H5Bpublic.h \
    H5HGprivate.h \
-   H5HGpublic.h
-H5Sselect.o: \
-   H5Sselect.c \
+   H5HGpublic.h \
+   H5Tprivate.h \
+   H5Tpublic.h \
+   H5Sprivate.h \
+   H5Spublic.h
+H5.o: \
+   H5.c \
    H5private.h \
    H5public.h \
    H5config.h \
+   H5ACprivate.h \
+   H5ACpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Ipublic.h \
+   H5Dpublic.h \
+   H5Bprivate.h \
+   H5Bpublic.h \
    H5Eprivate.h \
    H5Epublic.h \
-   H5Ipublic.h \
    H5Iprivate.h \
    H5MMprivate.h \
    H5MMpublic.h \
+   H5Pprivate.h \
+   H5Ppublic.h \
+   H5Zpublic.h \
    H5Sprivate.h \
    H5Spublic.h \
    H5Gprivate.h \
    H5Gpublic.h \
+   H5Oprivate.h \
+   H5Opublic.h \
+   H5HGprivate.h \
+   H5HGpublic.h \
+   H5Tprivate.h \
+   H5Tpublic.h
+H5AC.o: \
+   H5AC.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5ACprivate.h \
+   H5ACpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Ipublic.h \
+   H5Dpublic.h \
+   H5Eprivate.h \
+   H5Epublic.h
+H5B.o: \
+   H5B.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5ACprivate.h \
+   H5ACpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Ipublic.h \
+   H5Dpublic.h \
    H5Bprivate.h \
    H5Bpublic.h \
+   H5Eprivate.h \
+   H5Epublic.h \
+   H5MFprivate.h \
+   H5MFpublic.h \
+   H5MMprivate.h
+H5D.o: \
+   H5D.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5Iprivate.h \
+   H5Ipublic.h \
+   H5ACprivate.h \
+   H5ACpublic.h \
    H5Fprivate.h \
    H5Fpublic.h \
    H5Dpublic.h \
+   H5Dprivate.h \
+   H5Gprivate.h \
+   H5Gpublic.h \
+   H5Bprivate.h \
+   H5Bpublic.h \
    H5Oprivate.h \
    H5Opublic.h \
    H5HGprivate.h \
    H5HGpublic.h \
    H5Tprivate.h \
    H5Tpublic.h \
+   H5Sprivate.h \
+   H5Spublic.h \
    H5Zprivate.h \
-   H5Zpublic.h
-H5T.o: \
-   H5T.c \
+   H5Zpublic.h \
+   H5Eprivate.h \
+   H5Epublic.h \
+   H5HLprivate.h \
+   H5HLpublic.h \
+   H5MFprivate.h \
+   H5MFpublic.h
+H5E.o: \
+   H5E.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5Iprivate.h \
+   H5Ipublic.h \
+   H5Eprivate.h
+H5F.o: \
+   H5F.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5Aprivate.h \
+   H5Apublic.h \
+   H5Ipublic.h \
+   H5Gprivate.h \
+   H5Gpublic.h \
+   H5Bprivate.h \
+   H5Bpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Dpublic.h \
+   H5Dprivate.h \
+   H5Oprivate.h \
+   H5Opublic.h \
+   H5HGprivate.h \
+   H5HGpublic.h \
+   H5Tprivate.h \
+   H5Tpublic.h \
+   H5Sprivate.h \
+   H5Spublic.h \
+   H5Zprivate.h \
+   H5Zpublic.h \
+   H5Iprivate.h \
+   H5ACprivate.h \
+   H5ACpublic.h \
+   H5Eprivate.h \
+   H5Epublic.h \
+   H5MMprivate.h \
+   H5MMpublic.h
+H5Ffamily.o: \
+   H5Ffamily.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5Eprivate.h \
+   H5Epublic.h \
+   H5Ipublic.h
+H5Fistore.o: \
+   H5Fistore.c \
    H5private.h \
    H5public.h \
    H5config.h \
@@ -996,53 +945,79 @@ H5T.o: \
    H5Spublic.h \
    H5Zprivate.h \
    H5Zpublic.h \
-   H5Iprivate.h \
    H5Eprivate.h \
    H5Epublic.h \
-   H5MMprivate.h
-H5Tbit.o: \
-   H5Tbit.c \
+   H5MFprivate.h \
+   H5MFpublic.h
+H5Flow.o: \
+   H5Flow.c \
    H5private.h \
    H5public.h \
    H5config.h \
    H5Eprivate.h \
    H5Epublic.h \
    H5Ipublic.h \
-   H5Iprivate.h \
-   H5Tpkg.h \
-   H5HGprivate.h \
-   H5HGpublic.h \
    H5Fprivate.h \
    H5Fpublic.h \
    H5Dpublic.h \
-   H5Tprivate.h \
-   H5Tpublic.h \
-   H5Gprivate.h
-H5Tconv.o: \
-   H5Tconv.c \
-   H5Iprivate.h \
+   H5MMprivate.h \
+   H5MMpublic.h
+H5HL.o: \
+   H5HL.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5ACprivate.h \
+   H5ACpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
    H5Ipublic.h \
+   H5Dpublic.h \
+   H5Eprivate.h \
+   H5Epublic.h \
+   H5HLprivate.h \
+   H5HLpublic.h \
+   H5MFprivate.h \
+   H5MFpublic.h \
+   H5MMprivate.h
+H5MF.o: \
+   H5MF.c \
+   H5private.h \
    H5public.h \
    H5config.h \
+   H5Eprivate.h \
+   H5Epublic.h \
+   H5Ipublic.h
+H5O.o: \
+   H5O.c \
    H5private.h \
+   H5public.h \
+   H5config.h \
+   H5ACprivate.h \
+   H5ACpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Ipublic.h \
+   H5Dpublic.h \
    H5Eprivate.h \
    H5Epublic.h \
+   H5MFprivate.h \
+   H5MFpublic.h \
    H5MMprivate.h \
    H5MMpublic.h \
-   H5Tpkg.h \
+   H5Oprivate.h \
+   H5Opublic.h \
+   H5Gprivate.h \
+   H5Gpublic.h \
+   H5Bprivate.h \
+   H5Bpublic.h \
    H5HGprivate.h \
    H5HGpublic.h \
-   H5Fprivate.h \
-   H5Fpublic.h \
-   H5Dpublic.h \
    H5Tprivate.h \
    H5Tpublic.h \
-   H5Gprivate.h \
-   H5Gpublic.h \
-   H5Bprivate.h \
-   H5Bpublic.h
-H5Tinit.o: \
-   H5Tinit.c \
+   H5Sprivate.h
+H5S.o: \
+   H5S.c \
    H5private.h \
    H5public.h \
    H5config.h \
@@ -1052,44 +1027,69 @@ H5Tinit.o: \
    H5Epublic.h \
    H5MMprivate.h \
    H5MMpublic.h \
-   H5Tpkg.h \
-   H5HGprivate.h \
-   H5HGpublic.h \
+   H5Oprivate.h \
+   H5Opublic.h \
    H5Fprivate.h \
    H5Fpublic.h \
    H5Dpublic.h \
+   H5Gprivate.h \
+   H5Gpublic.h \
+   H5Bprivate.h \
+   H5Bpublic.h \
+   H5HGprivate.h \
+   H5HGpublic.h \
    H5Tprivate.h
-H5TB.o: \
-   H5TB.c \
-   H5private.h \
-   H5public.h \
-   H5config.h \
-   H5Iprivate.h \
-   H5Ipublic.h \
-   H5Eprivate.h
-H5V.o: \
-   H5V.c \
+H5Smpio.o: \
+   H5Smpio.c \
    H5private.h \
    H5public.h \
    H5config.h \
    H5Eprivate.h \
    H5Epublic.h \
    H5Ipublic.h \
+   H5Sprivate.h \
+   H5Spublic.h \
+   H5Gprivate.h \
+   H5Gpublic.h \
+   H5Bprivate.h \
+   H5Bpublic.h \
+   H5Fprivate.h \
+   H5Fpublic.h \
+   H5Dpublic.h \
    H5Oprivate.h \
    H5Opublic.h \
+   H5HGprivate.h \
+   H5HGpublic.h \
+   H5Tprivate.h \
+   H5Tpublic.h
+H5T.o: \
+   H5T.c \
+   H5private.h \
+   H5public.h \
+   H5config.h \
+   H5Dprivate.h \
+   H5Dpublic.h \
+   H5Ipublic.h \
    H5Fprivate.h \
    H5Fpublic.h \
-   H5Dpublic.h \
    H5Gprivate.h \
    H5Gpublic.h \
    H5Bprivate.h \
    H5Bpublic.h \
+   H5Oprivate.h \
+   H5Opublic.h \
    H5HGprivate.h \
    H5HGpublic.h \
    H5Tprivate.h \
    H5Tpublic.h \
    H5Sprivate.h \
-   H5Spublic.h
+   H5Spublic.h \
+   H5Zprivate.h \
+   H5Zpublic.h \
+   H5Iprivate.h \
+   H5Eprivate.h \
+   H5Epublic.h \
+   H5MMprivate.h
 H5Z.o: \
    H5Z.c \
    H5private.h \
diff --git a/src/H5.c b/src/H5.c
index 3b412db..072f6d0 100644
--- a/src/H5.c
+++ b/src/H5.c
@@ -62,7 +62,8 @@ FILE *fdopen(int fd, const char *mode);
 hbool_t                 library_initialize_g = FALSE;
 hbool_t                 thread_initialize_g = FALSE;
 hbool_t                 install_atexit_g = TRUE;
-static FILE		*H5_trace_g = NULL;
+H5_debug_t		H5_debug_g;		/*debugging info	*/
+static void		H5_debug_mask(const char*);
 
 typedef struct H5_exit {
     void                    (*func) (void);     /* Interface function to call during exit */
@@ -91,14 +92,40 @@ DESCRIPTION
 herr_t 
 H5_init_library(void)
 {
+    const char	*s = NULL;
+   
     FUNC_ENTER_INIT(H5_init_library, NULL, FAIL);
 
-    /* Install atexit() library cleanup routine */
-    if (install_atexit_g == TRUE)
-        if (HDatexit(&H5_term_library) != 0)
-            HRETURN_ERROR(H5E_FUNC, H5E_CANTINIT, FAIL,
-                          "unable to register atexit function");
+    /*
+     * Make sure the package information is updated.
+     */
+    HDmemset(&H5_debug_g, 0, sizeof H5_debug_g);
+    H5_debug_g.pkg[H5_PKG_A].name = "a";
+    H5_debug_g.pkg[H5_PKG_AC].name = "ac";
+    H5_debug_g.pkg[H5_PKG_B].name = "b";
+    H5_debug_g.pkg[H5_PKG_D].name = "d";
+    H5_debug_g.pkg[H5_PKG_E].name = "e";
+    H5_debug_g.pkg[H5_PKG_F].name = "f";
+    H5_debug_g.pkg[H5_PKG_G].name = "g";
+    H5_debug_g.pkg[H5_PKG_HG].name = "hg";
+    H5_debug_g.pkg[H5_PKG_HL].name = "hl";
+    H5_debug_g.pkg[H5_PKG_I].name = "i";
+    H5_debug_g.pkg[H5_PKG_MF].name = "mf";
+    H5_debug_g.pkg[H5_PKG_MM].name = "mm";
+    H5_debug_g.pkg[H5_PKG_O].name = "o";
+    H5_debug_g.pkg[H5_PKG_P].name = "p";
+    H5_debug_g.pkg[H5_PKG_S].name = "s";
+    H5_debug_g.pkg[H5_PKG_T].name = "t";
+    H5_debug_g.pkg[H5_PKG_V].name = "v";
+    H5_debug_g.pkg[H5_PKG_Z].name = "z";
 
+    /* Install atexit() library cleanup routine */
+    if (install_atexit_g == TRUE &&
+        HDatexit(&H5_term_library) != 0) {
+        HRETURN_ERROR(H5E_FUNC, H5E_CANTINIT, FAIL,
+		      "unable to register atexit function");
+    }
+    
     /*
      * Initialize interfaces that might not be able to initialize themselves
      * soon enough.
@@ -108,16 +135,9 @@ H5_init_library(void)
                       "unable to initialize type interface");
     }
 
-#ifdef H5_DEBUG_API
-    {
-	/* Turn on tracing? */
-	const char *s = getenv ("HDF5_TRACE");
-	if (s && isdigit(*s)) {
-	    int fd = (int)HDstrtol (s, NULL, 0);
-	    H5_trace_g = HDfdopen (fd, "w");
-	}
-    }
-#endif
+    /* Debugging? */
+    H5_debug_mask("-all");
+    H5_debug_mask(getenv("HDF5_DEBUG"));
 
     FUNC_LEAVE(SUCCEED);
 }
@@ -297,10 +317,91 @@ H5dont_atexit(void)
         install_atexit_g = FALSE;
 
     FUNC_LEAVE(SUCCEED);
-}                               /* end H5dont_atexit() */
+}
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5_debug_mask
+ *
+ * Purpose:	Set runtime debugging flags according to the string S.  The
+ *		string should contain file numbers and package names
+ *		separated by other characters. A file number applies to all
+ *		following package names up to the next file number. The
+ *		initial file number is `2' (the standard error stream). Each
+ *		package name can be preceded by a `+' or `-' to add or remove
+ *		the package from the debugging list (`+' is the default). The
+ *		special name `all' means all packages.
+ *
+ *		The name `trace' indicates that API tracing is to be turned
+ *		on or off.
+ *
+ * Return:	void
+ *
+ * Programmer:	Robb Matzke
+ *              Wednesday, August 19, 1998
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static void
+H5_debug_mask(const char *s)
+{
+    FILE	*stream = stderr;
+    char	pkg_name[32], *rest;
+    int		i, clear;
+	
+    while (s && *s) {
+	if (isalpha(*s) || '-'==*s || '+'==*s) {
+	    /* Enable or Disable debugging? */
+	    if ('-'==*s) {
+		clear = TRUE;
+		s++;
+	    } else if ('+'==*s) {
+		clear = FALSE;
+		s++;
+	    } else {
+		clear = FALSE;
+	    }
+
+	    /* Get the name */
+	    for (i=0; isalpha(*s); i++, s++) {
+		if (i<sizeof pkg_name) pkg_name[i] = *s;
+	    }
+	    pkg_name[MIN(sizeof(pkg_name)-1, i)] = '\0';
+
+	    /* Trace, all, or one? */
+	    if (!strcmp(pkg_name, "trace")) {
+		H5_debug_g.trace = clear?NULL:stream;
+	    } else if (!strcmp(pkg_name, "all")) {
+		for (i=0; i<H5_NPKGS; i++) {
+		    H5_debug_g.pkg[i].stream = clear?NULL:stream;
+		}
+	    } else {
+		for (i=0; i<H5_NPKGS; i++) {
+		    if (!strcmp(H5_debug_g.pkg[i].name, pkg_name)) {
+			H5_debug_g.pkg[i].stream = clear?NULL:stream;
+			break;
+		    }
+		}
+		if (i>=H5_NPKGS) {
+		    fprintf(stderr, "HDF5_DEBUG: ignored %s\n", pkg_name);
+		}
+	    }
+
+	} else if (isdigit(*s)) {
+	    int fd = (int)HDstrtol (s, &rest, 0);
+	    stream = HDfdopen (fd, "w");
+	    setvbuf (stream, NULL, _IOLBF, 0);
+	    s = rest;
+	} else {
+	    s++;
+	}
+    }
+}
+    
+
+/*-------------------------------------------------------------------------
  * Function:	H5version
  *
  * Purpose:	Returns the library version numbers through arguments. MAJNUM
@@ -1058,7 +1159,7 @@ H5_trace (hbool_t returning, const char *func, const char *type, ...)
     hssize_t		asize[16];
     hssize_t		i;
     void		*vp = NULL;
-    FILE		*out = H5_trace_g;
+    FILE		*out = H5_debug_g.trace;
 
     if (!out) return;	/*tracing is off*/
     va_start (ap, type);
diff --git a/src/H5AC.c b/src/H5AC.c
index b932f53..a51a3c2 100644
--- a/src/H5AC.c
+++ b/src/H5AC.c
@@ -649,9 +649,9 @@ H5AC_protect(H5F_t *f, const H5AC_class_t *type, const haddr_t *addr,
     H5AC_slot_t            *slot = NULL;
 
 #ifdef H5AC_DEBUG
-    static int		    ncalls = 0;
+    static int ncalls = 0;
     if (0 == ncalls++) {
-        fprintf(stderr, "H5AC: debugging cache (expensive)\n");
+	fprintf(stderr, "H5AC: debugging cache (expensive)\n");
     }
 #endif
 
@@ -857,55 +857,58 @@ H5AC_debug(H5F_t __unused__ *f)
     FUNC_ENTER(H5AC_debug, FAIL);
 
 #ifdef H5AC_DEBUG
-    fprintf(stderr, "H5AC: meta data cache statistics for file %s\n", f->name);
-    fprintf(stderr, "   %-18s %8s %8s %8s %8s+%-8s\n",
-            "Layer", "Hits", "Misses", "MissRate", "Inits", "Flushes");
-    fprintf(stderr, "   %-18s %8s %8s %8s %8s-%-8s\n",
-            "-----", "----", "------", "--------", "-----", "-------");
-
-    for (i = H5AC_BT_ID; i < H5AC_NTYPES; i++) {
-
-        switch (i) {
-        case H5AC_BT_ID:
-            strcpy(s, "B-tree nodes");
-            break;
-        case H5AC_SNODE_ID:
-            strcpy(s, "symbol table nodes");
-            break;
-        case H5AC_LHEAP_ID:
-            strcpy (s, "local heaps");
-            break;
-	case H5AC_GHEAP_ID:
-	    strcpy (s, "global heaps");
-	    break;
-        case H5AC_OHDR_ID:
-            strcpy(s, "object headers");
-            break;
-        default:
-            sprintf(s, "unknown id %d", i);
-        }
-
-        if (cache->diagnostics[i].nhits>0 ||
-	    cache->diagnostics[i].nmisses>0) {
-            miss_rate = 100.0 * cache->diagnostics[i].nmisses /
-			(cache->diagnostics[i].nhits+
-			 cache->diagnostics[i].nmisses);
-	} else {
-            miss_rate = 0.0;
-        }
-
-        if (miss_rate > 100) {
-            sprintf(ascii, "%7d%%", (int) (miss_rate + 0.5));
-        } else {
-            sprintf(ascii, "%7.2f%%", miss_rate);
-        }
-        fprintf(stderr, "   %-18s %8u %8u %7s %8u%+-9ld\n", s,
-                cache->diagnostics[i].nhits,
-                cache->diagnostics[i].nmisses,
-                ascii,
-                cache->diagnostics[i].ninits,
-		((long)(cache->diagnostics[i].nflushes) -
-		 (long)(cache->diagnostics[i].ninits)));
+    if (H5DEBUG(AC)) {
+	fprintf(H5DEBUG(AC), "H5AC: meta data cache statistics for file %s\n",
+		f->name);
+	fprintf(H5DEBUG(AC), "   %-18s %8s %8s %8s %8s+%-8s\n",
+		"Layer", "Hits", "Misses", "MissRate", "Inits", "Flushes");
+	fprintf(H5DEBUG(AC), "   %-18s %8s %8s %8s %8s-%-8s\n",
+		"-----", "----", "------", "--------", "-----", "-------");
+
+	for (i = H5AC_BT_ID; i < H5AC_NTYPES; i++) {
+
+	    switch (i) {
+	    case H5AC_BT_ID:
+		strcpy(s, "B-tree nodes");
+		break;
+	    case H5AC_SNODE_ID:
+		strcpy(s, "symbol table nodes");
+		break;
+	    case H5AC_LHEAP_ID:
+		strcpy (s, "local heaps");
+		break;
+	    case H5AC_GHEAP_ID:
+		strcpy (s, "global heaps");
+		break;
+	    case H5AC_OHDR_ID:
+		strcpy(s, "object headers");
+		break;
+	    default:
+		sprintf(s, "unknown id %d", i);
+	    }
+
+	    if (cache->diagnostics[i].nhits>0 ||
+		cache->diagnostics[i].nmisses>0) {
+		miss_rate = 100.0 * cache->diagnostics[i].nmisses /
+			    (cache->diagnostics[i].nhits+
+			     cache->diagnostics[i].nmisses);
+	    } else {
+		miss_rate = 0.0;
+	    }
+
+	    if (miss_rate > 100) {
+		sprintf(ascii, "%7d%%", (int) (miss_rate + 0.5));
+	    } else {
+		sprintf(ascii, "%7.2f%%", miss_rate);
+	    }
+	    fprintf(H5DEBUG(AC), "   %-18s %8u %8u %7s %8u%+-9ld\n", s,
+		    cache->diagnostics[i].nhits,
+		    cache->diagnostics[i].nmisses,
+		    ascii,
+		    cache->diagnostics[i].ninits,
+		    ((long)(cache->diagnostics[i].nflushes) -
+		     (long)(cache->diagnostics[i].ninits)));
+	}
     }
 #endif
 
diff --git a/src/H5B.c b/src/H5B.c
index a834bef..7491ed2 100644
--- a/src/H5B.c
+++ b/src/H5B.c
@@ -1680,7 +1680,7 @@ H5B_assert(H5F_t *f, const haddr_t *addr, const H5B_class_t *type,
     } *head = NULL, *tail = NULL, *prev = NULL, *cur = NULL, *tmp = NULL;
 
     FUNC_ENTER(H5B_assert, FAIL);
-    if (0 == ncalls++) {
+    if (0==ncalls++) {
 	fprintf(stderr, "H5B: debugging B-trees (expensive)\n");
     }
     /* Initialize the queue */
diff --git a/src/H5D.c b/src/H5D.c
index e033e93..36792a2 100644
--- a/src/H5D.c
+++ b/src/H5D.c
@@ -1370,8 +1370,11 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
 		    "collective read failed");
 #endif
 #ifdef H5D_DEBUG
-        fprintf (stderr, "H5D: data space conversion could not be optimized "
-		 "for this case (using general method instead)\n");
+	if (H5DEBUG(D)) {
+	    fprintf (H5DEBUG(D), "H5D: data space conversion could not be "
+		     "optimized for this case (using general method "
+		     "instead)\n");
+	}
 #endif
         H5E_clear ();
     }
@@ -1715,8 +1718,11 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
 		    "collective write failed");
 #endif
 #ifdef H5D_DEBUG
-	fprintf (stderr, "H5D: data space conversion could not be optimized "
-		 "for this case (using general method instead)\n");
+	if (H5DEBUG(D)) {
+	    fprintf (H5DEBUG(D), "H5D: data space conversion could not be "
+		     "optimized for this case (using general method "
+		     "instead)\n");
+	}
 #endif
 	H5E_clear ();
     }
diff --git a/src/H5Distore.c b/src/H5Distore.c
index efeb7d7..94d3590 100644
--- a/src/H5Distore.c
+++ b/src/H5Distore.c
@@ -1699,7 +1699,7 @@ H5F_istore_create(H5F_t *f, H5O_layout_t *layout /*out */ )
 /*-------------------------------------------------------------------------
  * Function:	H5F_istore_stats
  *
- * Purpose:	Print raw data cache statistics to the stderr stream.  If
+ * Purpose:	Print raw data cache statistics to the debug stream.  If
  *		HEADERS is non-zero then print table column headers,
  *		otherwise assume that the H5AC layer has already printed them.
  *
@@ -1722,23 +1722,22 @@ H5F_istore_stats (H5F_t *f, hbool_t headers)
     char	ascii[32];
     
     FUNC_ENTER (H5F_istore_stats, FAIL);
+    if (!H5DEBUG(AC)) HRETURN(SUCCEED);
 
     if (headers) {
-	fprintf(stderr, "H5F: raw data cache statistics for file %s\n",
+	fprintf(H5DEBUG(AC), "H5F: raw data cache statistics for file %s\n",
 		f->name);
-	fprintf(stderr, "   %-18s %8s %8s %8s %8s+%-8s\n",
+	fprintf(H5DEBUG(AC), "   %-18s %8s %8s %8s %8s+%-8s\n",
 		"Layer", "Hits", "Misses", "MissRate", "Inits", "Flushes");
-	fprintf(stderr, "   %-18s %8s %8s %8s %8s-%-8s\n",
+	fprintf(H5DEBUG(AC), "   %-18s %8s %8s %8s %8s-%-8s\n",
 		"-----", "----", "------", "--------", "-----", "-------");
     }
 
-#ifndef H5AC_DEBUG
-    /*
-     * If we're not debugging the H5AC layer then print these statistics only
-     * if we printed the headers that go with them.
-     */
-    if (headers) {
+#ifdef H5AC_DEBUG
+    if (H5DEBUG(AC)) headers = TRUE;
 #endif
+
+    if (headers) {
 	if (rdcc->nhits>0 || rdcc->nmisses>0) {
 	    miss_rate = 100.0 * rdcc->nmisses /
 			    (rdcc->nhits + rdcc->nmisses);
@@ -1751,12 +1750,10 @@ H5F_istore_stats (H5F_t *f, hbool_t headers)
 	    sprintf(ascii, "%7.2f%%", miss_rate);
 	}
 
-	fprintf(stderr, "   %-18s %8u %8u %7s %8d+%-9ld\n",
+	fprintf(H5DEBUG(AC), "   %-18s %8u %8u %7s %8d+%-9ld\n",
 		"raw data chunks", rdcc->nhits, rdcc->nmisses, ascii,
 		rdcc->ninits, (long)(rdcc->nflushes)-(long)(rdcc->ninits));
-#ifndef H5AC_DEBUG
     }
-#endif
 
     FUNC_LEAVE (SUCCEED);
 }
diff --git a/src/H5E.c b/src/H5E.c
index 71f5187..87de26c 100644
--- a/src/H5E.c
+++ b/src/H5E.c
@@ -123,7 +123,6 @@ H5E_t		H5E_stack_g[1];
  * Automatic error stack traversal occurs if the traversal callback function
  * is non null and an API function is about to return an error.  These should
  * probably be part of the error stack so they're local to a thread.
- * 
  */
 herr_t (*H5E_auto_g)(void*) = (herr_t(*)(void*))H5Eprint;
 void *H5E_auto_data_g = stderr;
diff --git a/src/H5F.c b/src/H5F.c
index b218931..fe04b9d 100644
--- a/src/H5F.c
+++ b/src/H5F.c
@@ -1062,11 +1062,10 @@ H5F_open(const char *name, uintn flags,
 	 * hdf5 data.
 	 */
 #ifdef H5F_DEBUG
-	fprintf(stderr, "H5F: resetting EOF from ");
-	H5F_addr_print(stderr, &addr1);
-	fprintf(stderr, " to ");
-	H5F_addr_print(stderr, &addr2);
-	fprintf(stderr, " (abs)\n");
+	if (H5DEBUG(F)) {
+	    HDfprintf(H5DEBUG(F), "H5F: resetting EOF from %a to %a (abs)\n",
+		      &addr1, &addr2);
+	}
 #endif
 	H5F_low_seteof(f->shared->lf, &addr2);
     }
@@ -1531,19 +1530,23 @@ H5F_close(H5F_t *f)
      * forgetting to close everything is not a major problem.
      */
     if (f->nopen>0) {
-#ifndef NDEBUG
-	fprintf(stderr, "H5F: H5F_close(%s): %u object header%s still "
-		"open (file close will complete when %s closed)\n",
-		f->name,
-		f->nopen,
-		1 == f->nopen ? " is" : "s are",
-		1 == f->nopen ? "that header is" : "those headers are");
+#ifdef H5F_DEBUG
+	if (H5DEBUG(F)) {
+	    fprintf(H5DEBUG(F), "H5F: H5F_close(%s): %u object header%s still "
+		    "open (file close will complete when %s closed)\n",
+		    f->name,
+		    f->nopen,
+		    1 == f->nopen ? " is" : "s are",
+		    1 == f->nopen ? "that header is" : "those headers are");
+	}
 #endif
 	f->close_pending = TRUE;
 	HRETURN(SUCCEED);
     } else if (f->close_pending) {
-#ifndef NDEBUG
-	fprintf(stderr, "H5F: H5F_close: operation completed\n");
+#ifdef H5F_DEBUG
+	if (H5DEBUG(F)) {
+	    fprintf(H5DEBUG(F), "H5F: H5F_close: operation completed\n");
+	}
 #endif
     }
 
diff --git a/src/H5Ffamily.c b/src/H5Ffamily.c
index fd876c0..464ffa1 100644
--- a/src/H5Ffamily.c
+++ b/src/H5Ffamily.c
@@ -177,9 +177,11 @@ H5F_fam_open(const char *name, const H5F_access_t *access_parms,
 	 * the same as the actual member size, but at least 1kB
 	 */
 #ifdef H5F_DEBUG
-	HDfprintf (stderr, "H5F: family member size has been increased "
-		   "from %a to %a\n", &(access_parms->u.fam.memb_size),
-		   &tmp_addr);
+	if (H5DEBUG(F)) {
+	    HDfprintf (H5DEBUG(F), "H5F: family member size has been "
+		       "increased from %a to %a\n",
+		       &(access_parms->u.fam.memb_size), &tmp_addr);
+	}
 #endif
 	if (tmp_addr.offset<1024) tmp_addr.offset = 1024;
 	lf->u.fam.memb_size = tmp_addr;
@@ -198,8 +200,11 @@ H5F_fam_open(const char *name, const H5F_access_t *access_parms,
 	 * member as the member size.
 	 */
 #ifdef H5F_DEBUG
-	HDfprintf (stderr, "H5F: family member size adjusted from %a to %a\n",
-		   &(access_parms->u.fam.memb_size), &tmp_addr);
+	if (H5DEBUG(F)) {
+	    HDfprintf (H5DEBUG(F), "H5F: family member size adjusted from "
+		       "%a to %a\n", &(access_parms->u.fam.memb_size),
+		       &tmp_addr);
+	}
 #endif
 	lf->u.fam.memb_size = tmp_addr;
 	for (membno=1; membno<lf->u.fam.nmemb; membno++) {
@@ -221,9 +226,10 @@ H5F_fam_open(const char *name, const H5F_access_t *access_parms,
      * member size but on a 32-bit machine this isn't possible.  The largest
      * file on a 32-bit machine is 2^32-1.
      */
-    if (lf->u.fam.memb_size.offset == ((size_t)1<<(sizeof(off_t)-1))) {
-	HDfprintf (stderr, "H5F: family member size may be too large: %a\n",
-		   &(lf->u.fam.memb_size));
+    if (H5DEBUG(F) &&
+	lf->u.fam.memb_size.offset == ((size_t)1<<(sizeof(off_t)-1))) {
+	HDfprintf(H5DEBUG(F), "H5F: family member size may be too large: %a\n",
+		  &(lf->u.fam.memb_size));
     }
 #endif
 	
diff --git a/src/H5Fistore.c b/src/H5Fistore.c
index efeb7d7..94d3590 100644
--- a/src/H5Fistore.c
+++ b/src/H5Fistore.c
@@ -1699,7 +1699,7 @@ H5F_istore_create(H5F_t *f, H5O_layout_t *layout /*out */ )
 /*-------------------------------------------------------------------------
  * Function:	H5F_istore_stats
  *
- * Purpose:	Print raw data cache statistics to the stderr stream.  If
+ * Purpose:	Print raw data cache statistics to the debug stream.  If
  *		HEADERS is non-zero then print table column headers,
  *		otherwise assume that the H5AC layer has already printed them.
  *
@@ -1722,23 +1722,22 @@ H5F_istore_stats (H5F_t *f, hbool_t headers)
     char	ascii[32];
     
     FUNC_ENTER (H5F_istore_stats, FAIL);
+    if (!H5DEBUG(AC)) HRETURN(SUCCEED);
 
     if (headers) {
-	fprintf(stderr, "H5F: raw data cache statistics for file %s\n",
+	fprintf(H5DEBUG(AC), "H5F: raw data cache statistics for file %s\n",
 		f->name);
-	fprintf(stderr, "   %-18s %8s %8s %8s %8s+%-8s\n",
+	fprintf(H5DEBUG(AC), "   %-18s %8s %8s %8s %8s+%-8s\n",
 		"Layer", "Hits", "Misses", "MissRate", "Inits", "Flushes");
-	fprintf(stderr, "   %-18s %8s %8s %8s %8s-%-8s\n",
+	fprintf(H5DEBUG(AC), "   %-18s %8s %8s %8s %8s-%-8s\n",
 		"-----", "----", "------", "--------", "-----", "-------");
     }
 
-#ifndef H5AC_DEBUG
-    /*
-     * If we're not debugging the H5AC layer then print these statistics only
-     * if we printed the headers that go with them.
-     */
-    if (headers) {
+#ifdef H5AC_DEBUG
+    if (H5DEBUG(AC)) headers = TRUE;
 #endif
+
+    if (headers) {
 	if (rdcc->nhits>0 || rdcc->nmisses>0) {
 	    miss_rate = 100.0 * rdcc->nmisses /
 			    (rdcc->nhits + rdcc->nmisses);
@@ -1751,12 +1750,10 @@ H5F_istore_stats (H5F_t *f, hbool_t headers)
 	    sprintf(ascii, "%7.2f%%", miss_rate);
 	}
 
-	fprintf(stderr, "   %-18s %8u %8u %7s %8d+%-9ld\n",
+	fprintf(H5DEBUG(AC), "   %-18s %8u %8u %7s %8d+%-9ld\n",
 		"raw data chunks", rdcc->nhits, rdcc->nmisses, ascii,
 		rdcc->ninits, (long)(rdcc->nflushes)-(long)(rdcc->ninits));
-#ifndef H5AC_DEBUG
     }
-#endif
 
     FUNC_LEAVE (SUCCEED);
 }
diff --git a/src/H5Flow.c b/src/H5Flow.c
index 5ddc299..73a5125 100644
--- a/src/H5Flow.c
+++ b/src/H5Flow.c
@@ -312,7 +312,11 @@ H5F_low_write(H5F_low_t *lf, const H5F_access_t *access_parms,
 	tmp_addr = *addr;
 	H5F_addr_inc(&tmp_addr, (hsize_t)size);
 	if (H5F_addr_gt(&tmp_addr, &(lf->eof))) {
-	    fprintf(stderr, "H5F: extending file w/o allocation\n");
+#ifdef H5F_DEBUG
+	    if (H5DEBUG(F)) {
+		fprintf(H5DEBUG(F), "H5F: extending file w/o allocation\n");
+	    }
+#endif
 	    lf->eof = tmp_addr;
 	}
 #ifdef HAVE_PARALLEL
diff --git a/src/H5Fprivate.h b/src/H5Fprivate.h
index 1dba61c..396b448 100644
--- a/src/H5Fprivate.h
+++ b/src/H5Fprivate.h
@@ -36,7 +36,7 @@
 
 /*
  * Feature: Define this constant on the compiler command-line if you want to
- *	    see some debugging messages on stderr.
+ *	    see some debugging messages on the debug stream.
  */
 #ifdef NDEBUG
 #  undef H5F_DEBUG
diff --git a/src/H5HL.c b/src/H5HL.c
index 88ee521..a960c80 100644
--- a/src/H5HL.c
+++ b/src/H5HL.c
@@ -643,8 +643,8 @@ H5HL_insert(H5F_t *f, const haddr_t *addr, size_t buf_size, const void *buf)
 
 	    if (max_fl->size < H5HL_SIZEOF_FREE(f)) {
 #ifdef H5HL_DEBUG
-		if (max_fl->size) {
-		    fprintf(stderr, "H5HL: lost %lu bytes at line %d\n",
+		if (H5DEBUG(HL) && max_fl->size) {
+		    fprintf(H5DEBUG(HL), "H5HL: lost %lu bytes at line %d\n",
 			    (unsigned long)(max_fl->size), __LINE__);
 		}
 #endif
@@ -670,17 +670,21 @@ H5HL_insert(H5F_t *f, const haddr_t *addr, size_t buf_size, const void *buf)
 		if (heap->freelist) heap->freelist->prev = fl;
 		heap->freelist = fl;
 #ifdef H5HL_DEBUG
-	    } else if (need_more > need_size) {
-		fprintf(stderr, "H5HL_insert: lost %lu bytes at line %d\n",
+	    } else if (H5DEBUG(HL) && need_more > need_size) {
+		fprintf(H5DEBUG(HL),
+			"H5HL_insert: lost %lu bytes at line %d\n",
 			(unsigned long)(need_more - need_size), __LINE__);
 #endif
 	    }
 	}
 
 #ifdef H5HL_DEBUG
-	fprintf(stderr, "H5HL: resize mem buf from %lu to %lu bytes\n",
-		(unsigned long)(heap->mem_alloc),
-		(unsigned long)(heap->mem_alloc + need_more));
+	if (H5DEBUG(HL)) {
+	    fprintf(H5DEBUG(HL),
+		    "H5HL: resize mem buf from %lu to %lu bytes\n",
+		    (unsigned long)(heap->mem_alloc),
+		    (unsigned long)(heap->mem_alloc + need_more));
+	}
 #endif
 	old_size = heap->mem_alloc;
 	heap->mem_alloc += need_more;
@@ -859,7 +863,10 @@ H5HL_remove(H5F_t *f, const haddr_t *addr, size_t offset, size_t size)
      */
     if (size < H5HL_SIZEOF_FREE(f)) {
 #ifdef H5HL_DEBUG
-	fprintf(stderr, "H5HL: lost %lu bytes\n", (unsigned long) size);
+	if (H5DEBUG(HL)) {
+	    fprintf(H5DEBUG(HL), "H5HL: lost %lu bytes\n",
+		    (unsigned long) size);
+	}
 #endif
 	HRETURN(SUCCEED);
     }
diff --git a/src/H5MF.c b/src/H5MF.c
index ddd29ec..b469f4b 100644
--- a/src/H5MF.c
+++ b/src/H5MF.c
@@ -71,12 +71,7 @@ H5MF_alloc(H5F_t *f, intn op, hsize_t size, haddr_t *addr/*out*/)
     assert(H5MF_META == op || H5MF_RAW == op);
     assert(size > 0);
     assert(addr);
-
-#if 0
-    HDfprintf (stderr, "A %Hu\n", size);
-#endif
     
-
     /* Fail if we don't have write access */
     if (0==(f->intent & H5F_ACC_RDWR)) {
 	HRETURN_ERROR (H5E_RESOURCE, H5E_CANTINIT, FAIL, "file is read-only");
@@ -226,8 +221,11 @@ H5MF_xfree(H5F_t *f, const haddr_t *addr, hsize_t size)
 	for (i=0; i<H5MF_NFREE; i++) {
 	    if (f->shared->fl_free[i].size<size) {
 #ifdef H5MF_DEBUG
-		fprintf(stderr, "H5MF_free: lost %lu bytes of file storage\n",
-			(unsigned long) f->shared->fl_free[i].size);
+		if (H5DEBUG(MF)) {
+		    fprintf(H5DEBUG(MF),
+			    "H5MF_free: lost %lu bytes of file storage\n",
+			    (unsigned long) f->shared->fl_free[i].size);
+		}
 #endif
 		f->shared->fl_free[i].addr = *addr;
 		f->shared->fl_free[i].size = size;
@@ -315,8 +313,8 @@ H5MF_realloc (H5F_t *f, intn op, hsize_t orig_size, const haddr_t *orig_addr,
     } else {
 	/* New size is not larger */
 #ifdef H5MF_DEBUG
-	if (new_size<orig_size) {
-	    HDfprintf (stderr, "H5MF: realloc lost %Hd bytes\n",
+	if (H5DEBUG(MF) && new_size<orig_size) {
+	    HDfprintf (H5DEBUG(MF), "H5MF: realloc lost %Hd bytes\n",
 		       orig_size-new_size);
 	}
 #endif
diff --git a/src/H5O.c b/src/H5O.c
index ca8e402..81efca7 100644
--- a/src/H5O.c
+++ b/src/H5O.c
@@ -238,9 +238,9 @@ H5O_open(H5G_entry_t *obj_ent)
     assert(obj_ent->file);
 
 #ifdef H5O_DEBUG
-    fprintf(stderr, ">");
-    H5F_addr_print(stderr, &(obj_ent->header));
-    fprintf(stderr, "\n");
+    if (H5DEBUG(O)) {
+	HDfprintf(H5DEBUG(O), "> %a\n", &(obj_ent->header));
+    }
 #endif
 
     /* Increment open-lock counters */
@@ -286,9 +286,9 @@ H5O_close(H5G_entry_t *obj_ent)
 	H5F_close(obj_ent->file);
     }
 #ifdef H5O_DEBUG
-    fprintf(stderr, "<");
-    H5F_addr_print(stderr, &(obj_ent->header));
-    fprintf(stderr, "\n");
+    if (H5DEBUG(O)) {
+	HDfprintf(H5DEBUG(O), "< %a\n", &(obj_ent->header));
+    }
 #endif
 
     FUNC_LEAVE(SUCCEED);
diff --git a/src/H5S.c b/src/H5S.c
index 7fb1088..48bde7c 100644
--- a/src/H5S.c
+++ b/src/H5S.c
@@ -105,73 +105,77 @@ H5S_term_interface(void)
     /*
      * Print statistics about each conversion path.
      */
-    for (i=0; i<H5S_nconv_g; i++) {
-	path = H5S_conv_g[i];
-	for (j=0; j<2; j++) {
-	    if (0==path->stats[j].gath_ncalls &&
-		0==path->stats[j].scat_ncalls &&
-		0==path->stats[j].bkg_ncalls) {
-		continue;
-	    }
-	    if (0==nprints++) {
-		fprintf(stderr, "H5S: data space conversion statistics "
-			"accumulated over life of library:\n");
-		fprintf(stderr, "   %-16s %10s %10s %8s %8s %8s %10s\n",
-			"Memory <> File", "Bytes", "Calls",
-			"User", "System", "Elapsed", "Bandwidth");
-		fprintf(stderr, "   %-16s %10s %10s %8s %8s %8s %10s\n",
-			"--------------", "-----", "-----",
-			"----", "------", "-------", "---------");
-	    }
-	    
-	    /* Summary */
-	    sprintf(buf, "%s %c %s",
-		    path->m->name, 0==j?'>':'<', path->f->name);
-	    fprintf(stderr, "   %-16s\n", buf);
-	    
-	    /* Gather */
-	    if (path->stats[j].gath_ncalls) {
-		H5_bandwidth(buf, (double)(path->stats[j].gath_nbytes),
-			     path->stats[j].gath_timer.etime);
-		HDfprintf(stderr,
-			  "   %16s %10Hu %10Hu %8.2f %8.2f %8.2f %10s\n",
-			  "gather",
-			  path->stats[j].gath_nbytes,
-			  path->stats[j].gath_ncalls,
-			  path->stats[j].gath_timer.utime, 
-			  path->stats[j].gath_timer.stime, 
-			  path->stats[j].gath_timer.etime,
-			  buf);
-	    }
-
-	    /* Scatter */
-	    if (path->stats[j].scat_ncalls) {
-		H5_bandwidth(buf, (double)(path->stats[j].scat_nbytes),
-			     path->stats[j].scat_timer.etime);
-		HDfprintf(stderr,
-			  "   %16s %10Hu %10Hu %8.2f %8.2f %8.2f %10s\n",
-			  "scatter",
-			  path->stats[j].scat_nbytes,
-			  path->stats[j].scat_ncalls,
-			  path->stats[j].scat_timer.utime, 
-			  path->stats[j].scat_timer.stime, 
-			  path->stats[j].scat_timer.etime,
-			  buf);
-	    }
-
-	    /* Background */
-	    if (path->stats[j].bkg_ncalls) {
-		H5_bandwidth(buf, (double)(path->stats[j].bkg_nbytes),
-			     path->stats[j].bkg_timer.etime);
-		HDfprintf(stderr,
-			  "   %16s %10Hu %10Hu %8.2f %8.2f %8.2f %10s\n",
-			  "background",
-			  path->stats[j].bkg_nbytes,
-			  path->stats[j].bkg_ncalls,
-			  path->stats[j].bkg_timer.utime, 
-			  path->stats[j].bkg_timer.stime, 
-			  path->stats[j].bkg_timer.etime,
-			  buf);
+    if (H5DEBUG(S)) {
+	for (i=0; i<H5S_nconv_g; i++) {
+	    path = H5S_conv_g[i];
+	    for (j=0; j<2; j++) {
+		if (0==path->stats[j].gath_ncalls &&
+		    0==path->stats[j].scat_ncalls &&
+		    0==path->stats[j].bkg_ncalls) {
+		    continue;
+		}
+		if (0==nprints++) {
+		    fprintf(H5DEBUG(S), "H5S: data space conversion "
+			    "statistics accumulated over life of library:\n");
+		    fprintf(H5DEBUG(S),
+			    "   %-16s %10s %10s %8s %8s %8s %10s\n",
+			    "Memory <> File", "Bytes", "Calls",
+			    "User", "System", "Elapsed", "Bandwidth");
+		    fprintf(H5DEBUG(S),
+			    "   %-16s %10s %10s %8s %8s %8s %10s\n",
+			    "--------------", "-----", "-----",
+			    "----", "------", "-------", "---------");
+		}
+
+		/* Summary */
+		sprintf(buf, "%s %c %s",
+			path->m->name, 0==j?'>':'<', path->f->name);
+		fprintf(H5DEBUG(S), "   %-16s\n", buf);
+
+		/* Gather */
+		if (path->stats[j].gath_ncalls) {
+		    H5_bandwidth(buf, (double)(path->stats[j].gath_nbytes),
+				 path->stats[j].gath_timer.etime);
+		    HDfprintf(H5DEBUG(S),
+			      "   %16s %10Hu %10Hu %8.2f %8.2f %8.2f %10s\n",
+			      "gather",
+			      path->stats[j].gath_nbytes,
+			      path->stats[j].gath_ncalls,
+			      path->stats[j].gath_timer.utime, 
+			      path->stats[j].gath_timer.stime, 
+			      path->stats[j].gath_timer.etime,
+			      buf);
+		}
+
+		/* Scatter */
+		if (path->stats[j].scat_ncalls) {
+		    H5_bandwidth(buf, (double)(path->stats[j].scat_nbytes),
+				 path->stats[j].scat_timer.etime);
+		    HDfprintf(H5DEBUG(S),
+			      "   %16s %10Hu %10Hu %8.2f %8.2f %8.2f %10s\n",
+			      "scatter",
+			      path->stats[j].scat_nbytes,
+			      path->stats[j].scat_ncalls,
+			      path->stats[j].scat_timer.utime, 
+			      path->stats[j].scat_timer.stime, 
+			      path->stats[j].scat_timer.etime,
+			      buf);
+		}
+
+		/* Background */
+		if (path->stats[j].bkg_ncalls) {
+		    H5_bandwidth(buf, (double)(path->stats[j].bkg_nbytes),
+				 path->stats[j].bkg_timer.etime);
+		    HDfprintf(H5DEBUG(S),
+			      "   %16s %10Hu %10Hu %8.2f %8.2f %8.2f %10s\n",
+			      "background",
+			      path->stats[j].bkg_nbytes,
+			      path->stats[j].bkg_ncalls,
+			      path->stats[j].bkg_timer.utime, 
+			      path->stats[j].bkg_timer.stime, 
+			      path->stats[j].bkg_timer.etime,
+			      buf);
+		}
 	    }
 	}
     }
diff --git a/src/H5T.c b/src/H5T.c
index 9be5749..15f2bef 100644
--- a/src/H5T.c
+++ b/src/H5T.c
@@ -727,20 +727,24 @@ H5T_term_interface(void)
 	    path->cdata.command = H5T_CONV_FREE;
 	    if ((path->func)(FAIL, FAIL, &(path->cdata), 0, NULL, NULL)<0) {
 #ifdef H5T_DEBUG
-		fprintf (stderr, "H5T: conversion function failed "
-			 "to free private data\n");
+		if (H5DEBUG(T)) {
+		    fprintf (H5DEBUG(T), "H5T: conversion function failed "
+			     "to free private data\n");
+		}
 #endif
 		H5E_clear(); /*ignore the error*/
 	    }
 #ifdef H5T_DEBUG
-	    if (path->cdata.stats->ncalls>0) {
+	    if (H5DEBUG(T) && path->cdata.stats->ncalls>0) {
 		if (0==nprint++) {
-		    HDfprintf (stderr, "H5T: type conversion statistics "
+		    HDfprintf (H5DEBUG(T), "H5T: type conversion statistics "
 			       "accumulated over life of library:\n");
-		    HDfprintf (stderr, "   %-16s %10s %10s %8s %8s %8s %10s\n",
+		    HDfprintf (H5DEBUG(T),
+			       "   %-16s %10s %10s %8s %8s %8s %10s\n",
 			       "Conversion", "Elmts", "Calls", "User",
 			       "System", "Elapsed", "Bandwidth");
-		    HDfprintf (stderr, "   %-16s %10s %10s %8s %8s %8s %10s\n",
+		    HDfprintf (H5DEBUG(T),
+			       "   %-16s %10s %10s %8s %8s %8s %10s\n",
 			       "----------", "-----", "-----", "----",
 			       "------", "-------", "---------");
 		}
@@ -749,7 +753,7 @@ H5T_term_interface(void)
 		nbytes *= path->cdata.stats->nelmts;
 		H5_bandwidth(bandwidth, (double)nbytes,
 			     path->cdata.stats->timer.etime);
-		HDfprintf (stderr,
+		HDfprintf (H5DEBUG(T),
 			   "   %-16s %10Hd %10d %8.2f %8.2f %8.2f %10s\n",
 			   path->name,
 			   path->cdata.stats->nelmts,
@@ -770,21 +774,22 @@ H5T_term_interface(void)
 
 #ifdef H5T_DEBUG
     /* Print debugging infor for the `noop' conversion */
-    if (H5T_conv_noop==H5T_find(NULL, NULL, H5T_BKG_NO, &cdata)) {
+    if (H5DEBUG(T) &&
+	H5T_conv_noop==H5T_find(NULL, NULL, H5T_BKG_NO, &cdata)) {
 	if (cdata->stats->ncalls>0) {
 	    if (0==nprint++) {
-		HDfprintf (stderr, "H5T: type conversion statistics "
+		HDfprintf (H5DEBUG(T), "H5T: type conversion statistics "
 			   "accumulated over life of library:\n");
-		HDfprintf (stderr, "   %-16s %10s %10s %8s %8s %8s %10s\n",
+		HDfprintf (H5DEBUG(T), "   %-16s %10s %10s %8s %8s %8s %10s\n",
 			   "Conversion", "Elmts", "Calls", "User",
 			   "System", "Elapsed", "Bandwidth");
-		HDfprintf (stderr, "   %-16s %10s %10s %8s %8s %8s %10s\n",
+		HDfprintf (H5DEBUG(T), "   %-16s %10s %10s %8s %8s %8s %10s\n",
 			   "----------", "-----", "-----", "----",
 			   "------", "-------", "---------");
 	    }
 	    nbytes = cdata->stats->nelmts;
 	    H5_bandwidth(bandwidth, (double)nbytes, cdata->stats->timer.etime);
-	    HDfprintf (stderr,
+	    HDfprintf (H5DEBUG(T),
 		       "   %-16s %10Hd %10d %8.2f %8.2f %8.2f %10s\n",
 		       "no-op",
 		       cdata->stats->nelmts,
@@ -3091,8 +3096,10 @@ H5Tregister_soft (const char *name, H5T_class_t src_cls, H5T_class_t dst_cls,
 		if ((path->func)(src_id, dst_id, &(path->cdata),
 				 0, NULL, NULL)<0) {
 #ifdef H5T_DEBUG
-		    fprintf (stderr, "H5T: conversion function failed "
-			     "to free private data.\n");
+		    if (H5DEBUG(T)) {
+			fprintf (H5DEBUG(T), "H5T: conversion function failed "
+				 "to free private data.\n");
+		    }
 #endif
 		    H5E_clear();
 		}
@@ -3170,8 +3177,10 @@ H5Tunregister (H5T_conv_t func)
 	    path->cdata.command = H5T_CONV_FREE;
 	    if ((func)(FAIL, FAIL, &(path->cdata), 0, NULL, NULL)<0) {
 #ifdef H5T_DEBUG
-		fprintf (stderr, "H5T: conversion function failed to "
+		if (H5DEBUG(T)) {
+		fprintf (H5DEBUG(T), "H5T: conversion function failed to "
 			 "free private data.\n");
+		}
 #endif
 		H5E_clear();
 	    }
@@ -4486,8 +4495,10 @@ H5T_path_find(const char *name, const H5T_t *src, const H5T_t *dst,
 	    }
 	    if ((func)(src_id, dst_id, &(path->cdata), 0, NULL, NULL)<0) {
 #ifdef H5T_DEBUG
-		fprintf (stderr, "H5T: conversion function init "
-			 "failed\n");
+		if (H5DEBUG(T)) {
+		    fprintf (H5DEBUG(T), "H5T: conversion function init "
+			     "failed\n");
+		}
 #endif
 		H5E_clear(); /*ignore the failure*/
 	    }
diff --git a/src/H5Z.c b/src/H5Z.c
index b6d44f8..f7a410d 100644
--- a/src/H5Z.c
+++ b/src/H5Z.c
@@ -86,45 +86,49 @@ H5Z_term_interface (void)
     int		dir, nprint=0;
     char	comment[16], bandwidth[32];
 
-    for (i=0; i<H5Z_table_used_g; i++) {
-	for (dir=0; dir<2; dir++) {
-	    if (0==H5Z_table_g[i].stats[dir].total) continue;
-
-	    if (0==nprint++) {
-		/* Print column headers */
-		HDfprintf (stderr, "H5Z: filter statistics accumulated "
-			   "over life of library:\n");
-		HDfprintf (stderr, "   %-16s %10s %10s %8s %8s %8s %10s\n",
-			   "Filter", "Total", "Errors", "User",
-			   "System", "Elapsed", "Bandwidth");
-		HDfprintf (stderr, "   %-16s %10s %10s %8s %8s %8s %10s\n",
-			   "------", "-----", "------", "----",
-			   "------", "-------", "---------");
-	    }
+    if (H5DEBUG(Z)) {
+	for (i=0; i<H5Z_table_used_g; i++) {
+	    for (dir=0; dir<2; dir++) {
+		if (0==H5Z_table_g[i].stats[dir].total) continue;
+
+		if (0==nprint++) {
+		    /* Print column headers */
+		    HDfprintf (H5DEBUG(Z), "H5Z: filter statistics "
+			       "accumulated over life of library:\n");
+		    HDfprintf (H5DEBUG(Z),
+			       "   %-16s %10s %10s %8s %8s %8s %10s\n",
+			       "Filter", "Total", "Errors", "User",
+			       "System", "Elapsed", "Bandwidth");
+		    HDfprintf (H5DEBUG(Z),
+			       "   %-16s %10s %10s %8s %8s %8s %10s\n",
+			       "------", "-----", "------", "----",
+			       "------", "-------", "---------");
+		}
 
-	    /* Truncate the comment to fit in the field */
-	    strncpy(comment, H5Z_table_g[i].name, sizeof comment);
-	    comment[sizeof(comment)-1] = '\0';
-
-	    /*
-	     * Format bandwidth to have four significant digits and units
-	     * of `B/s', `kB/s', `MB/s', `GB/s', or `TB/s' or the word
-	     * `Inf' if the elapsed time is zero.
-	     */
-	    H5_bandwidth(bandwidth,
-			 (double)(H5Z_table_g[i].stats[dir].total),
-			 H5Z_table_g[i].stats[dir].timer.etime);
-
-	    /* Print the statistics */
-	    HDfprintf (stderr,
-		       "   %s%-15s %10Hd %10Hd %8.2f %8.2f %8.2f "
-		       "%10s\n", dir?"<":">", comment, 
-		       H5Z_table_g[i].stats[dir].total,
-		       H5Z_table_g[i].stats[dir].errors,
-		       H5Z_table_g[i].stats[dir].timer.utime,
-		       H5Z_table_g[i].stats[dir].timer.stime,
-		       H5Z_table_g[i].stats[dir].timer.etime,
-		       bandwidth);
+		/* Truncate the comment to fit in the field */
+		strncpy(comment, H5Z_table_g[i].name, sizeof comment);
+		comment[sizeof(comment)-1] = '\0';
+
+		/*
+		 * Format bandwidth to have four significant digits and units
+		 * of `B/s', `kB/s', `MB/s', `GB/s', or `TB/s' or the word
+		 * `Inf' if the elapsed time is zero.
+		 */
+		H5_bandwidth(bandwidth,
+			     (double)(H5Z_table_g[i].stats[dir].total),
+			     H5Z_table_g[i].stats[dir].timer.etime);
+
+		/* Print the statistics */
+		HDfprintf (H5DEBUG(Z),
+			   "   %s%-15s %10Hd %10Hd %8.2f %8.2f %8.2f "
+			   "%10s\n", dir?"<":">", comment, 
+			   H5Z_table_g[i].stats[dir].total,
+			   H5Z_table_g[i].stats[dir].errors,
+			   H5Z_table_g[i].stats[dir].timer.utime,
+			   H5Z_table_g[i].stats[dir].timer.stime,
+			   H5Z_table_g[i].stats[dir].timer.etime,
+			   bandwidth);
+	    }
 	}
     }
 #endif
diff --git a/src/H5private.h b/src/H5private.h
index 0b2aba8..e0147e5 100644
--- a/src/H5private.h
+++ b/src/H5private.h
@@ -472,6 +472,49 @@ int64 HDstrtoll (const char *s, const char **rest, int base);
 extern char *strdup(const char *s);
 #define HDstrdup(S)             strdup(S)
 
+/*
+ * These macros check whether debugging has been requested for a certain
+ * package at run-time.  Code for debugging is conditionally compiled by
+ * defining constants like `H5X_DEBUG'.  In order to see the output though
+ * the code must be enabled at run-time with an environment variable
+ * HDF5_DEBUG which is a list of packages to debug.
+ *
+ * Note:  If you add/remove items from this enum then be sure to update the
+ *	  information about the package in H5_init_library().
+ */
+typedef enum {
+    H5_PKG_A,				/*Attributes			*/
+    H5_PKG_AC,				/*Meta data cache		*/
+    H5_PKG_B,				/*B-trees			*/
+    H5_PKG_D,				/*Datasets			*/
+    H5_PKG_E,				/*Error handling		*/
+    H5_PKG_F,				/*Files				*/
+    H5_PKG_G,				/*Groups			*/
+    H5_PKG_HG,				/*Global heap			*/
+    H5_PKG_HL,				/*Local heap			*/
+    H5_PKG_I,				/*Interface			*/
+    H5_PKG_MF,				/*File memory management	*/
+    H5_PKG_MM, 				/*Core memory management	*/
+    H5_PKG_O,				/*Object headers		*/
+    H5_PKG_P,				/*Property lists		*/
+    H5_PKG_S,				/*Data spaces			*/
+    H5_PKG_T,				/*Data types			*/
+    H5_PKG_V,				/*Vector functions		*/
+    H5_PKG_Z,				/*Raw data filters		*/
+    H5_NPKGS				/*Must be last			*/
+} H5_pkg_t;
+
+typedef struct H5_debug_t {
+    FILE		*trace;		/*API trace output stream	*/
+    struct {
+	const char	*name;		/*package name			*/
+	FILE		*stream;	/*output stream	or NULL		*/
+    } pkg[H5_NPKGS];
+} H5_debug_t;
+
+extern H5_debug_t		H5_debug_g;
+#define H5DEBUG(X)		(H5_debug_g.pkg[H5_PKG_##X].stream)
+
 /*-------------------------------------------------------------------------
  * Purpose:	These macros are inserted automatically just after the
  *		FUNC_ENTER() macro of API functions and are used to trace