为什么即使我有写权限也不能删除文件?

con*_*use 5 filesystem permissions

shell 会话应该说明一切:movie.avi尽管我有写权限,但我无法删除文件 ( )。我不明白问题是什么。我错过了什么吗?

confus@homeserver:/home/narur$ id
uid=1000(confus) gid=1000(confus) groups=1000(confus),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),106(lpadmin),117(sambashare),118(debian-transmission),1001(narur)

confus@homeserver:/home/narur$ ll | grep movie.avi 
-rw-rw----  1 narur narur 1,4G Jan 11 09:42 movie.avi

confus@homeserver:/home/narur$ rm movie.avi 
rm: cannot remove `movie.avi': Permission denied

# # # # SOME INFOS ON MY SYSTEM:
confus@homeserver:/home/narur$ lsb_release -dc
Description:    Ubuntu 12.10
Codename:   quantal
confus@homeserver:/home/narur$ uname -a
Linux conserve 3.5.0-21-generic #32-Ubuntu SMP Tue Dec 11 18:51:59 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
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Flo*_*sch 13

要删除文件,您不需要该文件的写入权限,但需要该文件所在文件夹的写入和执行权限。