Explicitly request GNU format. This will

disappear when GNU extended header keywords are working.

tests/incremen.sh

@@ -6,14 +6,28 @@
 
 set -e
 mkdir structure
-touch structure/file
-# FIXME: The sleep is necessary for the second tar to work.  Exactly why?
+echo x >structure/file
+
+# On Nextstep (and perhaps other 4.3BSD systems),
+# a newly created file's ctime isn't updated
+# until the next sync or stat operation on the file.
+ls -l structure/file >/dev/null
+
+# If the time of an initial backup and the creation time of a file contained
+# in that backup are the same, the file will be backed up again when an
+# incremental backup is done, because the incremental backup backs up
+# files created `on or after' the initial backup time.  Without the sleep
+# command, behaviour of tar becomes variable, depending whether the system
+# clock ticked over to the next second between creating the file and
+# backing it up.
 sleep 1
-tar cf archive --listed=list structure
-tar cfv archive --listed=list structure
+
+tar cf archive --format=gnu --listed=list structure
+tar cfv archive --format=gnu --listed=list structure
 echo -----
-touch structure/file
-tar cfv archive --listed=list structure
+sleep 1
+echo y >structure/file
+tar cfv archive --format=gnu --listed=list structure
 
 out="\
 structure/

tests/multiv01.sh

@@ -19,13 +19,13 @@ for block in " 1" " 2" " 3" " 4" " 5" " 6" " 7" " 8" \
   done
 done >file2
 
-tar -c --multi-volume --tape-length=10 \
+tar -c --format=gnu --multi-volume --tape-length=10 \
   --listed-incremental=t.snar \
   -f t1-pipe.tar -f t2-pipe.tar ./file1 ./file2
 
 mkdir extract-dir-pipe
 dd bs=4096 count=10 if=t2-pipe.tar |
-PATH=$PATH ${TRUSS} tar -f t1-pipe.tar -f - \
+PATH=$PATH ${TRUSS} tar --format=gnu -f t1-pipe.tar -f - \
       -C extract-dir-pipe -x --multi-volume \
       --tape-length=10 --read-full-records
 

tests/volume.sh

@@ -4,7 +4,7 @@
 . ./preset
 . $srcdir/before
 
-tar cfVT archive label /dev/null || exit 1
+tar -cf archive -V label -T /dev/null --format=gnu || exit 1
 
 tar xfV archive label || exit 1
 tar xfV archive 'la?el' || exit 1