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+# tools'fied mkhybrid to build HFS/ISO9660 hybrid image for mac68k and macppc
+
+(See src/distrib/cdrom/README how to fetch set binaries and build iso images)
+
+## What's this?
+
+This external/gpl2/mkhybrid provides tools'fied mkhybrid(8) to build
+HFS/ISO9660 hybrid CD images for mac68k and macppc install media,
+based on mkhybrid 1.12b5.1 in OpenBSD 7.3:
+ http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/gnu/usr.sbin/mkhybrid/src/
+
+## Changes from OpenBSD's one
+
+- pull sources in OpenBSD's src/gnu/usr.sbin/mkhybrid/src except libfile
+  into NetBSD's src/external/gpl2/mkhybrid/dist
+  (unnecessary files for tools builds are not imported)
+- pull 2 clause BSD licensed libfile sources from upstream cdrtools-3.01
+- pull Makefile in OpenBSD's src/gnu/usr.sbin/mkhybrid/mkhybrid
+  into NetBSD's src/external/gpl2/mkhybrid/bin
+- src/external/gpl2/mkhybrid/bin is prepared to build tools version
+  in src/tools/mkhybrid using src/tools/Makefile.host
+- tweak configure to pull several header files for NetBSD tools builds
+- appease various dumb warnings
+- pull -hide-rr-moved option from upstream mkisofs-1.13
+- pull -graft-points option from upstream mkisofs-1.13 and cdrtools-2.01
+- pull malloc related fixes in tree.c from upstream cdrtools-2.01
+
+## Current status
+
+- builds on NetBSD, ubuntu, and Cygwin hosts are tested
+
+See commit logs and diffs for more details.
+
+## TODO
+
+- add support to specify permissions via mtree-specfiles
+  as native makefs(8) for non-root build