为什么通配符在`sudo rm`语句中不起作用？

Question

I was trying to delete all files in log directory and using default bash shell on CentOS 6.5

[lei@ids7gueywjZ /]$ sudo ls -al /var/log/jenkins/
total 1541512
drwxr-x---   2 jenkins jenkins       4096 Jul 22 09:52 .
drwxr-xr-x. 10 root    root          4096 Jul 14 21:27 ..
-rw-r--r--   1 jenkins jenkins      31483 Jul 22 17:07 jenkins.log
-rw-r--r--   1 jenkins jenkins 1073606656 Jul 18 03:16 jenkins.log-20150718
-rw-r--r--   1 jenkins jenkins  504815011 Jul 19 03:30 jenkins.log-20150719.gz
[lei@ids7gueywjZ /]$ sudo rm -r /var/log/jenkins/*
rm: cannot remove `/var/log/jenkins/*': No such file or directory

I don't understand why rm -r /var/log/jenkins/* doesn't work? Is there some default shell configuration I was missing?

Answer 1

The wildcard expansion is done by the shell, not by rm .

And the shell does not have sudo rights, only rm does.

So since the shell does not have permission to read /var/log/jenkins , there is no expansion, and rm attempts to delete the file (not the wildcard) /var/log/jenkins/* -- which does not exist.

To get around this, you need a shell with sudo rights executing your rm :

sudo sh -c 'rm /var/log/jenkins/*'

Answer 2

The directory /var/log/jenkins has no rights for "other". Even if you run sudo rm -r /var/log/jenkins/* , the shell expansion is done by your user. You should either remove the whole direcotry ( suro rm -r /var/log/jenkinks ), or do everything as the appropriate user (I'd recommend su -ing with jenkins user).