chmod is used to change the commonly used read, write, and execute permissions on files. It can change these permission bits for the file owner, the file's group owner, and everyone else. It can also change the more esoteric ‘permissions’ (attributes, reall) like set-user-ID, set-group-ID, and ...

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Why can't I run programs on another partition in Linux?

So for convenience, I store all my data on my Windows partition so that I can access my data easily from both Linux and Windows. However, I tried compiling a C++ program with g++, and found out that I ...
29
votes
4answers
9k views

How to recover from a chmod -R 000 /bin?

And now I am unable to chmod it back.. or use any of my other system programs. Luckily this is on a VM I've been toying with, but is there any way to resolve this? The system is Ubuntu Server 12.10. ...
22
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4answers
57k views

How to get permission number by string : -rw-r--r--

I need to set the same chmod, how to get number for -rw-r--r-- ?
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2answers
674 views

relation between chmod and sudo on an executable file

What is the relationship between chmod and sudo on an executable file for a user? Are the cases that "a user needs sudo to run an executable" the same as the cases that "chmod hasn't set the ...
6
votes
3answers
4k views

File permission with setuid and octal 4000

When we set setuid to a file, we do the following in the terminal: chmod u+s filename This works fine. But the octal number 4000 is always associated with setuid (in books etc). I understand (to ...
4
votes
1answer
500 views

chmod doesn't work on folder 'd — — ---' permissions

In /var/www I've got a folder: d--------- 2 www-data www-data 4096 May 20 2012 update reported by ls -la. I'm logged in as root, but I can't change permissions or ownership. chown and chmod ...
1
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1answer
4k views

Set default permisson for newly folders and files in Linux

I'm using OpenSuSE and my computer has only 2 accounts: root and me.I have a directory /srv/www/htdocs/abc. I just want to set it up so that when new folders or files are created in this directory ...
8
votes
3answers
27k views

Recursive chmod only folders or only files via script or nautilus menu?

This has been discussed before here. What I'd like to know is how to turn these: Recursive chmod only files within this folder: find . -type f -exec chmod 0600 {} \; Recursive chmod only folders ...
3
votes
1answer
1k views

Why can't I chmod these files that I could earlier?

I was trying to add execute permissions to sh files in a folder. For that I mistakenly used: find . -print0 -iname '*.sh' | xargs -0 chmod -v 744 and the output was : mode of `.' changed from 0755 ...
19
votes
1answer
607 views

Why does chmod require disk space? Not-in-place algorithm?

I try to chmod some files and I get the error "disk quota exceeded": It's true that I don't have that much space remaining in the filesystem where I use chmod, namelynfs.mit.edu:/export/evodesign/...
3
votes
4answers
3k views

How can I change all of the contents inside of directory to what the default file ownership and permissions are?

I have moved contents of another drive into my home directory, but the permissions are not what they should be. First, I changed ownership by entering: ~$ sudo chown -R USERME /home/USERHOME/ ...
1
vote
4answers
1k views

chmod - change permissions on a file

I have a Python virtualenv, and the Python executable is located in the /bin directory. In this virtualenv I'll have to execute some unsafe code, that can damage my system. I tried to chmod a-r on the ...
1
vote
1answer
1k views

Changing permission from read only in linux?

I am trying to get the automatic brightness bug fixed in Linux Mint 17 based on the new Ubuntu release. In order to do this i had to create a file named 20-intel.conf in location /usr/...
1
vote
2answers
559 views

Why can user have lower permissions than group or other? Who can change them?

It is my understanding that the owner of a file user can have lower permissions than group or other. What is the justification for this? Can only root and the owner change the permissions on a file?...
1
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0answers
1k views

Save motion output videos in USB Drive

I'm using a USB drive in my Raspberry to store my website. Now I want also save my videos made with motion. I wasn't able to save in a folder different from /tmp/motion so googling I found I had to ...
1
vote
3answers
568 views

Reverse a chmod command on a directory

Is there a way to undo a chmod command on a directory in CentOS ?
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votes
2answers
111 views

Misuse of go-r *

I am working on a test server. Was logged in as root and issued cd / chmod go-r * I certainly revoked the write permissions for the users that I had created. Did I revoke the permissions (r/w/x) ...
1
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2answers
4k views

Find all directories, in which user has access to search and echo this directories in shell

I need to find all directories, in which user has access to search(command find) and echo this directories in shell. USER is read from ksh. for example: read user I know, if user want to use find ...
0
votes
2answers
857 views

Unable to access a folder through group permissions

In order to secure data on my webserver, I have moved the PHP includes to a folder called /var/www-includes (outside of /var/www, the server root). I also ran chown root:wwwadmin and chmod 770 on that ...
4
votes
1answer
2k views

chmod does not change permissions of certain directories

System file: ext4 I changed the owner of files to apache: with the command: chown -R apache: wp.localhost Then, I could not change the permissions of directories in wp.localhost nor the wp....
3
votes
1answer
7k views

Why can I not chmod a file?

[nathanb@ka /x/sim/nathanb/nbsim1] ls -al ,nvram -rw-r--r-- 1 root root 2097152 Jul 5 2011 ,nvram [nathanb@ka /x/sim/nathanb/nbsim1] sudo chmod a+w ,nvram chmod: changing permissions of ...
1
vote
2answers
2k views

How to exclude hidden files in recursive chmod?

I am having to do chmod -R 755 some_dir where 'some_dir' contains '.git' folders. Is there any way I can exclude hidden files and folder when doing recursive chmod? Note: chmoding .git folder is ...
3
votes
1answer
1k views

How to let a user execute a script owned by root? Setuid doesn't seem to work anymore [duplicate]

I have some bash scripts that I use with the user 'root' to manage iptable rules. The problem is that I want these things at the same time: The script must be owned by root Permissions must be 700 ...
3
votes
2answers
127 views

Accidentaly changed the permissions in / [duplicate]

Accidentally did : chmod -R 777 / Now, RHEL 6 is not booting up. What do I do? I have a DVD and can go into rescue mode. Can someone explain how do I reset all the permissions ? Update ...
2
votes
1answer
327 views

chmod 600 fails silently

Here is what happens: $ chmod 600 foobar.txt $ ls -l total 1 -rwx------ 0 sampablokuper sampablokuper 13 Feb 19 21:00 foobar.txt Why is the last line not reading as follows? -rw------- 0 ...
1
vote
1answer
437 views

list out owned file/directories and change its permissions

Can anyone please tell how can I change files/directories owned by me only. below is the command that list out files/directories owned by me find . -user <username>
0
votes
1answer
77 views

Explain the “@” symbol in this permissions example [duplicate]

I have a file on my Darwin system and the permissions are: -rwxr-xr-x@ User: read, write, execute Group: read, execute Other: read, execute What is the 11th notation the @ mean? In addition to ...
1
vote
1answer
94 views

Putting two accounts in group not giving read access to group members

I have an Apache based web site and am trying to allow the user to upload files to a drop box on one machine and then have them transferred to another. So I form a group for two users: www-data which ...
12
votes
5answers
23k views

Can't apply chmod to a file

I have a file on my HDD, cd /media/celebisait/5AC69788C6976355 There is my file called myFile.tar.gz. I do als -l, -rw------- 2 celebisait celebisait 1387745311 Jun 6 2013 myFile.tar.gz ...
0
votes
2answers
277 views

How can I give a permssion to all users for a path using the octal notation?

I'd like to give execute permissions on a path recursively so I can read a file in the directory. The chmod binary that I'm using on Android only supports the octal/numeric notation though. Normally ...
5
votes
1answer
486 views

What is chmod 6050 good for

Recently I came across to command: chmod -R 6050 /usr/lib/hadoop-yarn/bin/container-executor I don't know what that mean? I know file permissions like 777 etc. in a mode rwx for owner group others. ...
0
votes
3answers
1k views

How to compact a chmod UNIX command

Is there anyway to compact the follow UNIX command: chmod 755 scriptA.ksh | chmod 755 scriptB.ksh | chmod 755 scriptC.ksh | chmod 755 scriptD.ksh The above command makes every KornShell (ksh) ...
1
vote
2answers
1k views

How to modify the permission of jar file exactly same as other machine jar file? [duplicate]

I have two machines, In my machineA I have a jar file with these permissions - -rwxr-xr-x 1 cronus app 16758150 2013-03-19 13:35 exhibitor-1.5.1-jar-with-dependencies.jar In my another machineB, I ...
4
votes
3answers
449 views

restrict student account permissions, give faculty access

I have set up two user groups, students and faculty on Ubuntu 12.04 and created a number of students and faculty accounts. The problem is a student can currently see & read all of the files of a ...
2
votes
2answers
543 views

Make script executable from vi/vim

How can I run chmod +x on the script I'm creating in vi/vim so that it is executable? I tried :r chmod +x % but it didn't work.
0
votes
0answers
189 views

MySQL Backup folder permissions - Non downloadable by others

I created a PHP script which takes backup of the mysql database every day and then saves it to a folder called "BkPath". All the backups will be saved here. But am trying learn the chmod command to ...
2
votes
1answer
12k views

how do I mount a CIFS share so I can fully control the mounted volume on the client

It's a simple question: but I am in much pain over this situation, so here is the question: How can I "mount" a share so that a) the share is run on boot b) that I can control things like chown/chmod ...
3
votes
1answer
391 views

How to copy permissions from owner to others using `chmod`?

Is it possible to recursively copy the permissions of owner to group and others for all files in a given directory? PS: my chmod is 5.97
3
votes
4answers
20k views

permissions 755 on /home/<user>/

I am wondering why by default my directory /home/<user>/ has permissions set to 755. This allows other users to enter into directories and read files in my home. Is there any legitimate reason ...
5
votes
2answers
3k views

Chmod by Letters Vs Numbers

I was recently asked by a colleague to use chmod with letters instead of numbers. Apart from the obvious readability advantage is there any particular reason to use letters over numbers ?
2
votes
2answers
5k views

Unable to run 'sudo chmod +w /etc/hosts'

I am logged into my remote VM (running out of ESXi) as user xyz. I wanted to change my /etc/hosts to add some network names that were not visible by default. I first tried to run sudo vi /etc/hosts ...
1
vote
2answers
1k views

Executable located in location A how to run it in location B?

So, I've an executable in my debian server and this executable located in /home/human/ExecuteIt, still i cant figure it out how to run my executable in another location. In my case it is /home/human/...
1
vote
1answer
48 views

trying to search inside chmod with command [duplicate]

I am trying to find commands with the word "symbolic" inside the contents If I type man chmod and /symbolic you can see that chmod command has the line of "new modes of the file will ...
3
votes
3answers
959 views

'setfacl' permissions don't apply to directories created by git clone?

Here's how I am setting permissions for my website's root directory i.e. ~/public_html, where the files that my website serves are placed: sudo chgrp -R www-data ~/public_html chmod g+s ~/public_html ...
1
vote
1answer
942 views

Equivalent of full control, modify and write in linux

What is the equivalent of assigning Full control, Modify and Write permission, in Windows, to a particular user and group, in Linux? chgrp, chmod and chown seems quite limited in this case.
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votes
2answers
130 views

Is there a flag corresponding to x/X, but for s with chmod on Linux?

When using chmod (in my case part of coreutils 8.12), and recursively setting the x bit, there exists the convenient X (uppercase letter x), to set the bit only on directories. So if you wanted to ...
1
vote
2answers
120 views

FS permission scenario

How can I achieve this files & folders permissions scenario: Consider these folder: Folder A: 640 root apache /var/www/A/ Folder www: 640 root apache /var/www/ and this linux user: id user1: uid=...
6
votes
3answers
13k views

How can I revert a chmod on the etc directory?

I accidentally executed the following command on the etc directory: sudo chmod -R 700 /etc I know that I have done something very wrong. My terminal now prints: I have no name!@ubuntu: /$ How ...
2
votes
3answers
1k views

Safer way for granting permissions for self user?

I know sometimes we can do chmod 777 so we have a directory at our complete reach for accessing, reading and writing. But usually I prefer to do a sudo chown {myusername} {directory}. Obviously, the ...
8
votes
1answer
4k views

Is NTFS under linux able to save a linux file, with its chown and chmod settings?

I'm having some doubts about how to install and allow linux to correctly read/write to a NTFS formated harddrive used as backup of various machines (windows included, that's how I need NTFS). For now ...