Permissions are the unix way of controlling access to resources such as files, directories and devices and may be specified for an owner, group, or all users.

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Script with root permission [duplicate]

Possible Duplicate: Redirecting stdout to a file you don't have write permission on I am creating a script to change the brightness of my laptop. I discovered that I can do this using ...
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6answers
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File permission issues with shared folders under Virtual Box (Ubuntu Guest, Windows Host)

I am using Ubuntu on Virtual Box and I have a folder which is shared between the host (Windows) and the VM (Ubuntu). When I open any file in the share folder in Ubuntu, I can not change it as its ...
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3answers
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What are common rights for /tmp ? I unintentionnally set it all public recursively

I have abused sudo. I have created a really really short life temporary directory that I wanted to share between some users for a few hours... and I named this directory /some/path/tmp Unfortunately ...
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3answers
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How to “jail” a process without being root?

Were I root, I could simply create a dummy user/group, set file permissions accordingly and execute the process as that user. However I am not, so is there any way to achieve this without being root?
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How do I make a file NOT modifiable?

While logged in, I can do the following: mkdir foo touch foo/bar chmod 400 foo/bar chmod 500 foo Then I can open vim (not as root), edit bar, force a write with w!, and the file is modified. How ...
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7answers
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What to use to backup files, preserving ACLs?

When using the tar utility to store files in backups one loses the extended ACLs. Is there some commonly used and not hackish solution (like: create a script that will recrate the ACLs from scratch) ...
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2answers
939 views

How are file permissions calculated?

Using chmod I could set the permissions for a file, but if the parent ( .. ) directory had conflicting permissions, what would happen? And if I create a new file, using touch or something similiar, ...
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Which is more widely used: chmod 777 or chmod a+rwx [closed]

Out of the two options to change permissions: chmod 777 file.txt chmod a+rwx file.txt I am writing a document to send out to our customers, detailing that they need to change the file permissions ...
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Directory with +x permission, parents without it. When would this be useful?

Say I have a folder called folder in the following path: my_path = /a/b/c/d/e/folder and a file called file in that folder. Then, say I run this command to remove group permissions under /a/ > ...
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2answers
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USB drive permissions when automounting

On Debian there is the common problem, that you try to plug an ntfs formatted USB harddrive and then can't write to it as a regular user to it because the directory belongs to root. A little time ago ...
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5answers
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Making a directory protected from 'rm -rf'

I just lost some data in folder A which was inside folder B after doing rm -rf B. Before I could realize what have I done, it was all over. Now a lesson is learnt, I wish to make some of my folder ...
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8k views

Make all files under a directory read-only without changing permissions?

First, some background: /dev/md1 is a RAID-0 array serving as primary file store. It is mounted to /var/smb. /dev/md2 is another RAID-0 array storing backup snapshots taken from /dev/md1. It is ...
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1answer
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Preserve the permissions with rsync

Let's say I have a file a.txt in LINUX with permission of 0664. When I use rsync to copy the file to my Mac with rsync -r -t -v LINUX MAC, the file's permission becomes 0644. How can I keep the ...
18
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5answers
1k views

Find files that a user can write, efficiently with minimal process creation

I am root. I would like to know whether a non-root user has write access to some files - thousands of them. How to do it efficiently while avoiding process creation?
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5answers
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VSFTPD, 553 Could not create file. - permissions?

I've set up VSFTPD on Amazon EC2, with the Amazon Linux AMI. I created a user and can now succesfully connect via ftp. However, if I try to upload something I get the error message "553 Could not ...
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3answers
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What is a process GID and what purpose does it serve?

Reading mod_wsgi's documentation I found you can choose which group to run the worker processes as. I can understand group ownership of files and how only a user who belongs to that group can achieve ...
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2answers
5k views

Can I allow users to chmod a file not owned by them?

I would like to allow users to chmod a file that is owned by root or some user that is not themselves. I have chmod'ed the file to 777 and I get "operation not permitted". I have added the user to the ...
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1answer
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Writing raw images safely to USB sticks

Trying lots of different linux, on all kinds of hardware I find my self typing commands like this quite often: sudo dd if=xubuntu-13.10-desktop-amd64.iso of=/dev/sdc bs=10240 Needless to say, ...
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What are the settings to correct vsftpd “500 OOPS: cannot change directory” error?

My question is what settings do I need to change and/or commands to run to allow me to log into my vsftpd system? I am getting this error, when I login using ftp instead of sftp: Name ...
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2answers
1k views

Which user group can use the 'tap' net device?

I use the 'tap' net device with KVM to get my vm connect to the Internet. But I have to be root, or use 'sudo', which is inconvenient. I think I can put my user account into some group so I can access ...
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3answers
872 views

lxc: running virtualbox inside a container

I've install virtualbox inside an lxc container. However when I try to start a VM I get the message: kernel driver not accessible (rc=1909) ....permission problem with /dev/vboxdrv. This obviously ...
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2answers
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setuid and setgid confusion

I'm trying to fully grasp the concept of setuid and setgid, and I'm not quite sure in what way permissions are actually elevated. Let me provide an example: Users userA (groups: userA groupA) userB ...
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2answers
6k views

How to insert text into a root-owned file using sudo? [duplicate]

Possible Duplicate: Redirecting stdout to a file you don't have write permission on Running a command like sudo echo 'text' >> /file.txt fails with: bash: /file.txt: Permission ...
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2answers
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I can't delete a file that I have write permissions for as a group member

$ touch testfile $ chmod g+w testfile $ sudo adduser user2 user1 $ stat -c'%a %A' testfile 664 -rw-rw-r-- $ su user2 Password: $ groups user2 user1 $ rm testfile rm: cannot remove `testfile': ...
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1answer
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Is it possible to disable file permissions on a ext3 or ext4 file-system?

Is it possible to disable file permissions on an ext3/4 file-system? Just wondering if it's possible to completely disable or ignore file permissions on a ext3 or ext4 file system. Perhaps a mounting ...
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2answers
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How is file ownership affected across different systems?

As I understand Unix file systems, any file on a unix system must belong to a group and a user of the said system. A file cannot belong to a group or user that does not exist on the system. From that ...
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3answers
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bash: /dev/stderr: Permission denied

After upgrading to a new release version, my bash scripts start spitting errors: bash: /dev/stderr: Permission denied in previous versions Bash would internally recognize those file names (which is ...
6
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1answer
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Why cannot a user change group ownership of his own files? [duplicate]

Why cannot a user change the group permissions of files which he owns. Let's suppose I have user martin: $ ls -lAd /home/martin/ drwx------ 8 martin martin 4096 Apr 20 01:06 /home/martin/ For some ...
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2answers
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How to grant non-root user access to device files

I have device file that appears in /dev when a specific board is plugged in. The read and write operations to it work just fine, but in order to open the device file the program needs to be executed ...
6
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2answers
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Why do I get an “rsync: failed to set times on … : Operation not permitted (1)” error on Ubuntu 10.10 with SME Server 7.4? [duplicate]

I am trying to cron an rsync via ssh between two fileservers that are running SME Server 7.4 and Ubuntu 10.10, respectively. The first rsync worked just fine (for reasons that I do not know), but now, ...
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3answers
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find files which have a higher permission than xxx

I want to find all files which have a higher permission than e.g. 640. Perhaps this would work with a find and exec command. But my knowledge isn't sufficient for such a task.
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1answer
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Difference between owner/root and RUID/EUID

I am relatively new to the concepts mentioned in the question and reading about them from different sources only makes them more confusing. So this is what I understood so far: When we are given ...
4
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2answers
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CentOS - Issue with write permissions

I am running CentOS 6.4 and I have installed Wordpress on it. (along with LAMP) Now the problem is, that I cannot make any write changes to any files in the wordpress editor: eg. header.php, ...
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2answers
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how to initialize `/etc/group`?

After editing /etc/group, How this update starts functioning without restarting the system in Unix? Is there any command we need to run?
4
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2answers
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encfs with expect access denied

If I execute script #!/usr/bin/expect set pass [lindex $argv 0] spawn encfs -v {CRIPT_DIR} {MNT_DIR} -o nonempty expect "*EncFS Password:*" send "$pass\r" expect eof expect script output: ...
3
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1answer
214 views

How to create a user with minimalistic permissions on OpenBSD?

I want to run the webbrowser (xxxterm) with a different user (XY) on an OpenBSD Desktop (different user from the one I use daily). I will reach the Browser with ssh -X in the local machine (or are ...
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4answers
5k views

Permissions to deny SSH users from accessing other user's folders

I am currently running Fedora on a network computer, acting as a host to other users who will SSH into my terminal to do their work. However I realised that they are also able to access my /home ...
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3answers
234 views

Permissions for a submission script

I'm a TA for an introductory Python programming class (all work is done from the terminal), and I'm writing a project submission script. Ideally I want a directory setup like this: submissions/ ...
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1answer
109 views

Different write behavior for owner and member of group despite 775 permissions

I have mounted a remote share via my fstab using the line: //path/to/target /media/f cifs gid=<mygroup's id>,dir_mode=0775,file_mode=0775 0 0 As a result, everything under /media/f winds up ...
2
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3answers
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Allow a user to view the home directory of other users via sudo

I am new to system administration. We have a lab set up where we have a server and client machines. The client machines have LDAP users which has the work area for all the users in the centralized ...
2
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1answer
3k views

NAS box mounted via CIFS - problem with permissions

I'm running the latest version of Ubuntu, and have mounted a SMB share via a line in rc.local. The share mounts correctly, and I can browse files freely, create new files, and then delete them ...
2
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1answer
706 views

How to assign correct permissions to both webserver and svn?

I've an issue with files ownerships in unix. I have a drupal website and the "files" folder needs to be owned by "www-data" in order to let the users to upload files with php. However I'm now using ...
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3answers
134 views

To Rsync files where permission denied

I want to find those files which I cannot copy to another location such that I could do Rsync. I have an external HDD and my system´s HDD. The external HDD has files which my system is missing. I ...
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3answers
3k views

Run Linux “motion” app as user

I'm trying to run Motion app on a Linux box. For various security reasons, I'd rather run it as regular user than sudo. However, when I run "service motion start" without the sudo in front, it says: ...
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Make web project writable by apache and other user

I am running ubuntu 12.04 LTS . To be able to view my web project in the browser I did the following: chown -R www-data:www-data /var/www/project Now I wanted to open the project in netbeans but it ...
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1answer
184 views

Shared partition permission management

I am willing to try a dual boot arch/lmde setup on my laptop next week, but I've ran into a problem: I want to have a shared data storage where my downloads, documents etc would reside and could be ...
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2answers
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How to non-invasively test for write access to a file?

In a shell script, how do I easily and non-invasively test for write access to a file without actually attempting to modify the file? I could parse the output of stat, but that seems really complex, ...
9
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1answer
931 views

Cannot expand asterisk without proper permission

Can someone explain to me the following? $ ls -ld /temp/sit/build/ dr-xr-s--- 3 asdf qwer 4096 Jan 31 2012 /temp/sit/build/ $ ls -ld /temp/sit/build/* ls: /temp/sit/build/*: Permission denied So ...
9
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2answers
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recursively change file permission but not directories?

I was doing a mass recursive change of permissions of some files that I had migrated to a unix system. I changed them to ug+rw, but then I found that I could not traverse subdirectories. I looked at ...
8
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3answers
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“echo 3 > /proc/sys/vm/drop_caches” - Permission denied as root

I am currently having some issues with the cache. It is a little too much right now so I wanted to clear it. I googled and found this little command: sync && echo 3 > ...