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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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: ...
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2answers
507 views

How to hide someone else's directories from a user?

I have several folders: /home/user1/ -u user1 -G user1 /home/user2/ -u user2 -G user2 /home/user3/ -u user3 -G user3 I created three users user1, user2, user3. Each user has own group. Any user can ...
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1answer
1k 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 ...
3
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3answers
2k 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 ...
107
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7answers
7k views

How to chmod without /usr/bin/chmod?

Today I was told a tale by a Unix trainer, a tale where the root password got leaked to the students, and one of the fellas removed the execute permission from /usr/bin/chmod itself. How do you ...
2
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3answers
256 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 ...
2
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3answers
336 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 ...
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3answers
381 views

Directory appears as file?

So we copied some photos in a directory across to a NTFS partition last night, and they were viewable from ubuntu. Today the directory is not accessible from Windows, and when we booted back into ...
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4answers
1k views

chmod recursive permission on thousands of files

This is a more general question about 'chmoding' recursively. I have this script which at some point needs to change the permissions recursively in a folder which has a few hundred thousand files. ...
0
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1answer
33 views

how to display I/O file on shell [closed]

I am writing shell script and I need to display my output at the same time however it doesn't work with 2> somefile.txt and if I do | tee -a somefilel it will not overwrite which I need to . <> ...
1
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1answer
261 views

Permission error to access mounted directory in localhost

OK, I formatted my flash to ext4 file system, changed all the permissions to 777 and mounted it to /var/www/html/web. Now, when i access localhost/web it gives the following error: "You don't have ...
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1answer
177 views

Changed file access to read only but I can still write to the file. Why?

I am running a small embedded system built using buildroot. I have come across this strange behaviour when trying to set up my file permissions on the target device. To illustrate what confuses me I ...
28
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4answers
4k 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. ...
0
votes
1answer
74 views

Removing access privileges to backup while maintaining current setup

I have a giant directory, and I am dealing with a backup. I would like to store this backup in as safe of a way as possible. One of the ways of doing that is removing rwx privileges through chmod. ...
1
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1answer
969 views

Safe to change owner of OS X system folders?

I'm trying to get Homebrew to work. That program's diagnosis tool gives me these suggestions: You should probably chown /usr/local/etc ... You should probably chown them: ...
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2answers
2k views

Unable to change permissions of file system root

When I write ls -la the output is : tusharmakkar08-Satellite-C660 tusharmakkar08 # ls -la total 88 drwxr-x---+ 10 root root 4096 Apr 18 19:43 . drwxr-xr-x 4 root root 4096 Mar 18 17:35 .. ...
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1answer
127 views

chmod allowing write when I am not setting it

I've got a perl script which systematically changes permissions. The first thing the script does is remove all permissions. It does this by calling chmod(from perl). I did this as I found the set guid ...
3
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2answers
86 views

How can a user restrict their own group rights without being root?

How can I change my user rights from rwx to r-x at the group level? I'm trying to ensure that I cannot touch any data belonging to other users when I am developing and debugging my scripts. Once I've ...
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3answers
1k views

find . .[^.]* -type f -print0 | xargs -0 sudo chmod 664; does not work

I am using this command to set permissions for files recursively clime@vm6879 /srv/www-php/steeltrading $ find . .[^.]* -type f -print0 | xargs -0 sudo chmod 664 But after executing that command ...
1
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1answer
394 views

chmod and chown not working in sudo called script

Based on this Serverfault question, my git user has permission in sudoers to run a wrapper script to move files into my webroot with git. Everything is working fine except for the chmod and chown ...
3
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7answers
4k views

Convert ls -l output format to chmod format

Say I have the following output from ls -l: drwxr-xr-x 2 root root 4096 Apr 7 17:21 foo How can I automatically convert this to the format used by chmod? For example: $ echo drwxr-xr-x | ...
0
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2answers
182 views

Files created by 'make' aren't getting executable permissions by default

I'm trying to build a project, and when I use the command make, I get the following errors: /bin/sh: line 4: .deps/ipset_bitmap_ipmac.Tpo: Permission denied make[2]: *** [ipset_bitmap_ipmac.lo] Error ...
1
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1answer
142 views

Able to delete file without permission [duplicate]

I've been experimenting with file permissions and ownership lately, and I tried this: touch a sudo chown root:root a sudo chmod 000 a I can't read, write, or execute the file, but I can still ...
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2answers
1k 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 ...
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1answer
98 views

Why is ./filename required to run executable script? [duplicate]

After creating a Python script file, test.py, in my home directory, and running chmod +x test.py to make it executable, and placing #!usr/bin/env as the file header, I expected to be able to run the ...
2
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1answer
4k views

script failing with “chmod: … Operation not permitted”

A script of mine works fine when I run it, but fails when run by a different user, with an error of the form chmod: changing permissions of `/A/B/C/D/E': Operation not permitted (Here /A/B/C/D/E is ...
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2answers
706 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 ...
1
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2answers
426 views

How to make a path world-readable?

To make some item X world-readable, it is not enough for it to have the right permissions: each component of the absolute path leading to it must also have the right permissions. (My understanding, ...
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2answers
650 views

chmod wont work - no error message

Everytime I try to change the permissions of a file with chmod on my Ubuntu with a command like chmod 744 /media/DATEN/Dokumente/Coding/Python/DirFileFuncts.py it doesnt work. I tried octal and =rwx ...
1
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1answer
990 views

Allow all group members to create directories and files

There are 2 users sftp_user apache Both users belong to the updaters group as well as other groups. New directories and files are created in the /updates/ directory. drwxrwsr-x 8 sftp updaters ...
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0answers
140 views

External HDD read/write permission changing from a cron job

So, I run an overnight python script that runs a backup of our web data in the /var/www directory, then moves the backups to an external HDD in /media. The script in scheduled in the sudo crontab ...
4
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2answers
5k views

Why does “chmod 1777” and “chmod 3777” both set the sticky bit?

To set the sticky bit on a directory, why do the commands chmod 1777 and chmod 3777 both work?
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1answer
104 views

Securely running LAMP under a specific user

I'm setting up a sandbox type of server that will be used by a couple users as a development environment and knowledge base. The server will have a web frontend so I've installed Apache, MySQL and ...
2
votes
1answer
300 views

What does it mean if a directory has only x (executable) permission for certain user/group?

I stumbled across the directory /etc/ssl/private on Ubuntu (12.04), it has following permission: drwx--x--- 2 root ssl-cert 4096 7月 8 2012 private/ I wonder what does this mean for group ...
3
votes
1answer
156 views

Change who is able to chmod

Is there a way to change who can chmod (change the permissions of) a particular file? It is only the owner of the file (without sudo-ing it), if my experimentation has been correct? But what I want ...
4
votes
1answer
504 views

Clear setuid permission using numeric mode

On an Ubuntu Linux I have a directory with the setuid bit set (drwsr-xr-x) which I want to unset. Neither chmod 755 nor chmod 0755 nor chmod 00755 (I though maybe the first 0 is interpreted as just ...
2
votes
1answer
381 views

Hide parent directory but allow to view dir

I would like the following result on my UNIX system: ls -l /users/test -> permission denied, or any other way so I can't see the content of it. ls -l /users/test/testdir/ -> shows all files in the ...
2
votes
1answer
4k 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 ...
5
votes
1answer
2k views

what is the difference between “chmod 775” and “chmod 2755”?

Question What is the difference between "chmod 775" and "chmod 2755" ?
6
votes
4answers
3k views

When does chmod fail?

Under what circumstances will chmod fail? I looked at the man page but it only specifies usage and doesn't go into details about what circumstances it won't work in. I'd assume chmod will work if: ...
3
votes
1answer
171 views

How to create a folder which will change its contents’ ownership to what the folder has?

In a GNU/Linux OS there is no way to change ownership of a file until you are root. But what if I want to hide my system’s username e.g. before sending a file to someone, because some things like tar ...
0
votes
1answer
240 views

Unable to change file permissions [duplicate]

Possible Duplicate: No effect of umask and chmod on mounted drives I am not able to change file permissions using chmod from the user who owns the file as well as from root. I am using ...
2
votes
4answers
3k views

How to make executable of all files excluding a few file types?

I have a folder containing many C source file and the same number of its compiled output files. I set executable bit to all this files but for some reason it was lost, making them not executable. (I ...
2
votes
4answers
9k views

How to permanently change the file/directory permission [closed]

How do I change the permission of file/directories such that I am able to create, edit, delete files/directories anywhere in my system? Currently I am using Ubuntu 12.04. I tried sudo chmod 777 -r ...
15
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2answers
10k views

Get the chmod numerical value for a file

In FreeBSD and also in Linux, how can I get the numerical chmod value of a file? For example, 644 instead of -rw-r--r--? I need an automatic way for a Bash script.
2
votes
3answers
163 views

User with read access to /home

Pardon my ignorance but I can't seem to come up with a solution to this one. I'd like to create a user that has read access to every user's home catalog located in /home. Do I need acl's for this or ...
1
vote
1answer
464 views

External drive chmod does nothing

Why is it that I can do chmod on my files when they are on my laptops hard drive, but when i make files on my external drive, i can't change their access rights. I do: chmod 755 somefile, and on my ...
2
votes
3answers
2k views

Change Folder Permissions

I started off with changing to the folder I want to change permissions for, and that is the opt folder. $ cd /opt/ test@testVM:/opt$ So I tried changing the permissions for this folder now using: ...
3
votes
1answer
947 views

Giving SSH users read-only access to a directory

I'm running Fedora 17 and I want to give several users access to files on my secondary hard drives on /run/media/haukur/. This is what I initially did: chmod -R 755 /run/media/ But every time I ...
5
votes
2answers
294 views

Is it possible to represent the +X symbolic permission with an octal value?

Is it possible to represent the +X symbolic permission with an octal value? The chmod(1) man page says: execute/search only if the file is a directory or already has execute permission for some ...