Linux refers to the family of Unix-like computer operating systems using the Linux kernel. If your question is about a certain distribution only, use a more specific tag.

learn more… | top users | synonyms

23
votes
3answers
1k views

Have a file named ~ (tilde) in my home-directory (Linux)

I just noticed that I have a file called ~ in my ~-directory. $ ls -la ~ ... -rw-r----- 1 x1 x1 733962240 Mar 1 17:55 ~ ... Any idea how I can mv or rm it?
23
votes
4answers
5k views

How to lock a file against deletion but still make it writeable?

I want to make a file locked against deletion but still be writeable. How do I do this? The file in question is a truecrypt volume as a file on a NAS SMB Network share, so I don't want to ...
23
votes
3answers
1k views

Sudo su vs su linux

If I enter in the password to su when prompted, it doesnt work while sudo su does. Also, when a command is executed using sudo (command), does sudo automatically execute it by root by default (since ...
23
votes
4answers
1k views

Why is it possible to change the password of an admin user on linux?

A few days ago, a friend of mine, wanted to show me that he can use my linux even if I don't tell him my password. He entered in GRUB, selected the recovery mode option. My first problem is that he ...
23
votes
9answers
49k views

How to convert Word (doc) to PDF in linux?

I have a set of files in .doc format, that need to be converted to .pdf format. I am using Ubuntu linux.
23
votes
2answers
49k views

How do you set a password for transmission-daemon, the BitTorrent client server?

The config file is ambiguous, and keeps getting overwritten when you restart the daemon in Debian, anyway. In /etc/transmission-daemon/settings.json, there are these options: rpc-username ...
23
votes
7answers
4k views

Why create many partitions?

I have noticed that when installing Ubuntu some people create multiple partitions for directories. Like one for root, one for home, one for boot. What is the advantage to doing this over installing ...
23
votes
4answers
6k views

tmux disregarding the configuration file

I just installed tmux on Ubuntu 10.04 and tried to remap the prefix key to C-a by creating the file ~/.tmux.conf with these lines: set-option -g prefix C-a unbind-key C-b When starting tmux, both ...
23
votes
6answers
26k views

Batch-convert files for encoding

How can I batch-convert files in a directory for their encoding (e.g. ANSI->UTF-8) with a command or tool? For single files an editor helps, but how to do the mass files job?
23
votes
4answers
18k views

what does the dot mean at the end of -rw-r--r--. How do you set it with chmod?

I see that some of the files in my directories under Linux have a . at the end of the permissions listing. what does the dot mean at the end of -rw-r--r--. How do you set it with chmod ?
23
votes
4answers
67k views

How to upload one file by FTP from command line?

I need to upload a single file to FTP server from Ubuntu. This operation should be done in a script (in non-interactive mode). What is the right syntax for ftp? I'm trying this, to no avail: $ ftp ...
23
votes
5answers
2k views

Does running commands verbosely make them slower?

I've found myself using the -v flag for lots of applications less and less (especially for trivial stuff like tar and cp). However, when I did and I was, say, unzipping a large file, it would take ...
23
votes
3answers
4k views

Can a process be frozen temporarily in linux?

I was wondering if there is a way to freeze any process for a certain amount of time? What I mean is that: is it possible for one application (probably running as root) to pause the execution of ...
23
votes
2answers
46k views

Linux - Mount device with specific user rights

How can I mount a device with specific user rights on start up? I still have some problems figuring it out. I would like to mount the divide with uid=1000 and gid=1000. My current entry to the ...
23
votes
2answers
34k views

How do I increase VirtualBox resolution past 800x600 in Linux? [duplicate]

Possible Duplicate: Ubuntu on VirtualBox can only show resolution of 800x600 - how to change it? No matter what I do I cannot get the resolution past 800x600. If I am using a Windows ...
23
votes
3answers
5k views

How can I log all process launches in Linux

I would like to get a log of all processes that are launched with the time that they were launched and the arguments they were launched with. Is this possible in Linux?
22
votes
6answers
8k views

/usr/local or /opt?

How do you generally proceed for your package installations on Linux, for packages that are not part of your distrib's repos? On my side I am used to install in /opt. But since, I saw this doc on the ...
22
votes
4answers
56k views

How can I add a regular user to the sudoers file?

How can I add more users to the "sudoers" file?
22
votes
7answers
33k views

How to auto detect text file encoding?

There are many plain text files which were encoded in variant charsets. I want to convert them all to UTF-8, but before running iconv, I need to know its original encoding. Most browsers have an ...
22
votes
3answers
1k views

Subverting the execute flag on Linux systems. Why is this possible?

Whilst reading this, I found the following exploit: % cp /usr/bin/id ~ % chmod -x ~/id % ls -al ~/id -rw-r--r-- 1 edd edd 22020 2012-08-01 15:06 /home/edd/id % ~/id zsh: permission denied: ...
22
votes
3answers
13k views

How to add a command in vim editor?

If suppose my source code file name is "foo.c". While editing and debugging i always execute this command:- :!gcc -g foo.c -o foo;gdb foo Can I add a custom command to Vim such that If i type ...
22
votes
6answers
1k views

Learning the basics of Linux/Unix [closed]

I would like to learn the basics of Linux; In contrast to tutorials that teach how to do common tasks with Ubuntu or something. I'm looking for a structured introduction, not a reference. Also I would ...
22
votes
3answers
9k views

How do I execute multiple commands when using find?

I'm trying to run multiple commands on things I have found, how can I achieve this? find . -exec cmd1; cmd2 does not seem to work; it instead runs cmd2 after cmd1 has been executed on every file.
22
votes
7answers
6k views

How can I merge the gnome clipboard and the X selection?

I'm constantly frustrated by the two separate clipboards in X/Gnome. I'm constantly doing things like control-C to copy, and then middle-click to paste, and getting the wrong data. Or select ...
22
votes
2answers
1k views

Is it possible to compile a Darwin Distro from source, like you can a build a Linux Distro?

I have read through and undertaken Linux From Scratch (and BLFS) and I was wondering, can I follow this guide to create a Darwin Distro by substituting the xnu kernel? Would the process be vastly ...
21
votes
3answers
4k views

How accurate is `md5sum`?

When using md5sum to verify the integrity of a file, how accurate is the process? Does a verified MD5 mean that EVERY bit is exactly the same, or is there a threshold that must be broken before ...
21
votes
2answers
838 views

How to create a directory named '-p' under Linux with Bash? [duplicate]

In Bash, how could I create a directory named -p? mkdir -p failed. mkdir "-p" failed. mkdir "\-p" failed. mkdir \-p failed.
21
votes
7answers
25k views

How can I keep a process alive after closing the putty session?

I am using putty to interact with Linux server. I have started a process using putty. The process is running and will take 5-6 hours. I want that process to keep running after I close the putty ...
21
votes
3answers
16k views

Case Insensitive search from find command?

I am not able to figure out how can I do case-insensitive search using the find command. I tried find . -name -i pattern And it does not work.
21
votes
2answers
522 views

What problems does udev actually solve?

For that matter, what exactly was wrong with a bunch of static files in /dev? It's apparently unsatisfactory enough for developers to have reinvented this wheel by my count 3 times now (devfs -> udev ...
21
votes
5answers
1k views

Why doesn't Gzip compression eliminate duplicate chunks of data?

I just did a little experiment where I created a tar archive with duplicate files to see if it would be compressed, to my awe, it was not! Details follow (results indented for reading pleasure): $ dd ...
21
votes
8answers
13k views

Linux: Compare Directory Structure Without Comparing Files

What is the best and simplest way to compare two directory structures without actually comparing the data in files. This works fine: diff -qr dir1 dir2 But it's really slow because it's comparing ...
21
votes
3answers
4k views

What does the 'rc' in `.bashrc`, etc. mean?

Well, this is embarrassing. I feel like I just realised I don't know a loyal colleague's name after working with them for 10 years. "Hey, er... *cough!*, thanks for that great job you did on setting ...
21
votes
3answers
18k views

How do you find the parent process of a zombie process?

How do you find the parent process of zombie processes? When the child process is something where the parent is not entirely obvious... Is there some way to list processes in tree format or ...
21
votes
14answers
3k views

How to become a Linux superuser? [closed]

What process/reference/book/faq/tutorial/quickstart/primer/etc would you recommend to a lifelong Windows guy who wants to become a Linux superuser? EDIT Perhaps I should provide a little bit of ...
21
votes
8answers
30k views

How to extract text with OCR from a PDF on Linux?

How do I extract text from a PDF that wasn't built with an index? It's all text, but I can't search or select anything. I'm running Kubuntu, and Okular doesn't have this feature.
21
votes
2answers
16k views

Is it possible to install the Helvetica font on linux?

I don't know too much about the licensing issues surrounding fonts, but I would like to install Helvetica on my machine for my own personal use. I haven't been able to find a whole lot about this on ...
21
votes
9answers
38k views

Any Linux BitTorrent client with support for Magnet links? [closed]

Is there any Linux application (bonus points for being console/headless) that supports Magnet links - like the ones provided now by some famous "bay" for pirate BitTorrent users?
21
votes
4answers
1k views

Can unexpected power loss harm a Linux install?

I am developing an application on a Linux embedded board (runs Debian) e.g. Raspberry Pi, Beagle Board/Bone, or olimex. The boards works on an environment that the electricity is cut unexpectedly (it ...
21
votes
2answers
21k views

What is /dev/mem?

Presumably it's somehow related to memory? What would sudo cat /dev/urandom > /dev/mem do? Trash all RAM? All non-kernel virtual memory? None of the above?
21
votes
4answers
8k views

What is the different between 'locate' and 'find' in Linux?

Why there are two so similar command in Linux? and normally what are the circumstances to use each of them?
21
votes
2answers
1k views

Enable Emacs-like keybindings scheme for all QT applications

As for GTK apps under Gnome environment it's possible to set all applications to use Emacs-like input scheme: $ gconftool --set -t string /desktop/gnome/interface/gtk_key_theme Emacs $ gconftool ...
21
votes
2answers
1k views

Use vim to edit ANY text on Linux

I come from the Mac world, where I use http://www.hogbaysoftware.com/products/quickcursor to edit text from anywhere in Vim. Is there anything like that on Linux ? I'm already using "It's All Text" ...
20
votes
5answers
5k views

What does the little squiggly ~ do in Linux?

I have two instances of it being used and I am wondering what each does: service=~ mv ~/Desktop/Service$version.tgz $service What does the little squiggly ~ do? Then, after that that, what would ...
20
votes
7answers
27k views

Which is more efficient - tar or zip compression? What is the difference between tar and zip?

I'm working in Linux environment and want to know about tar and zip commands. Which is more efficient - tar or zip? I also need to know the differences between the tar and zip commands. Can anyone ...
20
votes
5answers
78k views

Checking what PHP version I'm running on Linux?

I'm running Centos 5 and I need to know what version of PHP I'm running, is there a command for this which I can run?
20
votes
5answers
2k views

Are Linux commands interchangeable with Unix commands?

I find that some commands, for example, ls and pwd, can be used on both Linux and Unix systems. Is it that all Linux commands can be used in the Unix systems, and all Unix commands can be used in ...
20
votes
7answers
52k views

Copy directory contents using 'cp' command

How do you copy all the contents of one directory into another? For example: $ cd /home/newuser $ cp -a /backup/olduser/* . The problem with the above is that the globing pattern '*' matches the ...
20
votes
3answers
14k views

How to analyse disk usage in command line linux?

du and df are nice, but I don't know how to filter the data they provide the way I do with SequoiaView. I would like to know which are the largest folders and the largest files in a glance.
20
votes
4answers
21k views

How do I get the size of a Linux or Mac OS X directory from the command-line?

What command do I use to find the size of all the files (recursively) in a Linux or Mac OS X directory?