对dir来说没有x是不可以知道打开dir,至于r我就不太清楚怎么说
在 2011年1月31日 上午12:28,forest chen <anyform...@gmail.com>写道: > 2011/1/30 foolhunger <foolhun...@gmail.com> > > > 比如:在对一个有r权限没有x权限的dir进行ls > > -l的时候,可以显示出dir里的文件名,但是相关属性都是???(本人用bash),个人的理解是没有x就不能访问inode,所以无法显示属性。 > > > > 关于这点,在网上查了一下,找到一个解释,与你说的吻合. 具体看下文解释.页面链接为 > http://content.hccfl.edu/pollock/aunix1/filepermissions.htm > > > Execute Permission for Directories > > > > The chdir() system call is one of many that requires execute permission > on > > a directory. Of course a directory isn't really a program that you can > run > > even if it has execute permission. The execute bit is reused rather than > > waste space with additional permission bits. > > > > Besides controlling a user's ability to cd into some directory, the > > execute permission is required on a directory to use the stat() system > > call on files within that directory. The stat() system called is used to > > access the information in a file's inode, and must be done before you can > > open or delete (via the unlink() system call) that file. (See Note< > http://content.hccfl.edu/pollock/aunix1/filepermissions.htm#>.) > > > > > > Because of its role in file access the execute bit on a directory is > > sometimes called *search* permission. For example, to read a file > foo/bar, > > you must have read permission for the file itself, but before the file > can > > be accessed you must first search the directory foo for the inode of file > > bar. This requires search (x) permission on the directory foo. (Note > you > > don't need read permission on the directory in this case! You only need > > read permission on a directory to list its contents.) > > > -------------- 下一部分 -------------- > 一个HTML附件被移除... > URL: < > https://lists.ubuntu.com/archives/ubuntu-zh/attachments/20110131/63cb7a75/attachment.html > > > -- > ubuntu-zh mailing list > ubuntu-zh@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/ubuntu-zh > -------------- 下一部分 -------------- 一个HTML附件被移除... URL: <https://lists.ubuntu.com/archives/ubuntu-zh/attachments/20110131/aa659ec6/attachment.html> -- ubuntu-zh mailing list ubuntu-zh@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-zh