Question

我在Ubuntu bash中遇到了一个有趣的行为，我无法完全理解。如果我将扩展文件属性添加到文件然后更改它 - 属性将从文件中删除。从我的观点来看，这是可以的。

user@user:~/tmp$ echo "aaa" > testattr
user@user:~/tmp$ setfattr --name "user.test" --value "Tested" testattr 
user@user:~/tmp$ getfattr --name "user.test" testattr
# file: testattr
user.test="Tested"
user@user:~/tmp$ vi testattr 
< change something in file and save it > 
user@user:~/tmp$ getfattr --name "user.test" testattr
testattr: user.test: No such attribute

但是如果我使用bash在文件中写一些东西 - 文件属性就在它的位置。任何人都可以解释这种行为吗？

user@user:~/tmp$ echo "aaa" > testattr
user@user:~/tmp$ setfattr --name "user.test" --value "Tested" testattr 
user@user:~/tmp$ getfattr --name "user.test" testattr
# file: testattr
user.test="Tested"
user@user:~/tmp$ echo "bbb" > testattr
user@user:~/tmp$ getfattr --name "user.test" testattr
# file: testattr
user.test="Tested"

Answer 1

vi正在删除已编辑的文件并将其替换为新文件。这就是为什么不保留属性的原因。

这是文件上的操作日志。

$ mkdir test
$ touch test/file
$ inotifywait -m -r test
Setting up watches.  Beware: since -r was given, this may take a while!
Watches established.
# vi is now running in another shell
test/ OPEN file
test/ CREATE .file.swp
test/ OPEN .file.swp
test/ CREATE .file.swpx
test/ OPEN .file.swpx
test/ CLOSE_WRITE,CLOSE .file.swpx
test/ DELETE .file.swpx
test/ CLOSE_WRITE,CLOSE .file.swp
test/ DELETE .file.swp
test/ CREATE .file.swp
test/ OPEN .file.swp
test/ MODIFY .file.swp
test/ ATTRIB .file.swp
test/ CLOSE_NOWRITE,CLOSE file
test/ OPEN file
test/ CLOSE_NOWRITE,CLOSE file
test/ MODIFY .file.swp
test/ CREATE 4913
test/ OPEN 4913
test/ ATTRIB 4913
test/ CLOSE_WRITE,CLOSE 4913
test/ DELETE 4913
test/ MOVED_FROM file     # old file moved
test/ MOVED_TO file~
test/ CREATE file         # new file created
test/ OPEN file
test/ MODIFY file
test/ CLOSE_WRITE,CLOSE file
test/ ATTRIB file
test/ ATTRIB file
test/ MODIFY .file.swp
test/ DELETE file~
test/ CLOSE_WRITE,CLOSE .file.swp
test/ DELETE .file.swp

请参阅this answer以禁用该行为。

扩展文件属性和bash

1 个答案: