I got a question in the android emulator which use Yaffs2 file system:
When I create or delete a file in a directory, the mtime and ctime of
the directoy do not change. This issue does not appear in other
filesystems.
# cd /data
#
# mkdir test
# /data/busybox stat test
File: "test"
Size: 2048 Blocks: 4 IO Block: 4096 directory
Device: 1f01h/7937d Inode: 551 Links: 1
Access: (0777/drwxrwxrwx) Uid: ( 0/ UNKNOWN) Gid: ( 0/ UNKNOWN)
Access: 2009-05-21 03:22:21.000000000
Modify: 2009-05-21 03:22:21.000000000
Change: 2009-05-21 03:22:21.000000000
# cd test
# /data/busybox touch aaa
# /data/busybox stat aaa
File: "aaa"
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: 1f01h/7937d Inode: 561 Links: 1
Access: (0666/-rw-rw-rw-) Uid: ( 0/ UNKNOWN) Gid: ( 0/ UNKNOWN)
Access: 2009-05-21 03:23:15.000000000
Modify: 2009-05-21 03:23:15.000000000
Change: 2009-05-21 03:23:15.000000000
# cd ..
# /data/busybox stat test
File: "test"
Size: 2048 Blocks: 4 IO Block: 4096 directory
Device: 1f01h/7937d Inode: 551 Links: 1
Access: (0777/drwxrwxrwx) Uid: ( 0/ UNKNOWN) Gid: ( 0/ UNKNOWN)
Access: 2009-05-21 03:22:21.000000000
Modify: 2009-05-21 03:22:21.000000000
Change: 2009-05-21 03:22:21.000000000
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