Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs.

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10
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2answers
21k views

Subsystem for UNIX-based Applications in Windows 7

Noticed a thing called Subsystem for UNIX-based Applications in the Turn Windows features on and off dialog under Windows 7. Never seen it before, and it seems interesting. What exactly is it really? ...
18
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9answers
11k views

Is Mac OS X open source?

I learned recently (on superuser) that Mac OS X uses the bash shell. I also know that OS X has a UNIX core. I was searching for information about OS X and Open Source on google, but what I found was ...
13
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4answers
7k views

How can I recursively grep paticular files in a directory

I'm new to linux and grep, and trying to find my way around. By using find -name *.java I am able to find the names of all of the java files in a particular directory. Suppose I want to count the ...
10
votes
4answers
9k views

How do I set an environmental variable for a GNOME session?

On my system, for apps that use SDL, I need to set an environmental variable: export SDL_AUDIODRIVER=alsa to get the sound to work properly. How do I set up my GNOME session so that this variable ...
4
votes
2answers
220 views

shell dotfiles and *rcs: what's a sane setup?

A bash user will eventually end up with .bashrc, .bash_profile, .profile, and maybe some more. Now, each file gets loaded unders particular situations, and it all leads to confusion and frustration. ...
2
votes
4answers
2k views

Looking for a command to check for on-chip L3 cache size on a Unix system

I am looking for a command to check for on-chip L3 cache size on a Unix system.
29
votes
2answers
13k views

Is it a bad idea to use the same private ssh key on multiple computers?

I recently bought a laptop from which I need to access the same remote hosts that I do from my desktop. It occurred to me that it might be possible to simply copy the private key file from my desktop ...
2
votes
2answers
2k views

Finding folders that contain changed files since date

So, I have a directory with lots of sub-directories Something like... main main/folder1 main/folder2 main/folder2/otherfolder1 main/folder2/otherfolder2 etc... Is there an easy way for me to ...
2
votes
9answers
302 views

To mkdir `*/pictures`

My folder tree . |-- 1 |-- 2 |-- 3 ... |-- 777 I would like to create the folder pictures to each folder. I run unsuccesfully mkdir */pictures One way is of course creating 777 mkdir -commands ...
1
vote
2answers
10k views

To change $USER in OS X's terminal

I would like an other way to change my current user than by GUI. It would be great that if you can change the user as fast as you can your login shell by chsh. How can you change the user in OS X's ...
2
votes
2answers
591 views

How do I set a unix process to autorun in a particular run level?

I have a stand alone server application that I would like to run automatically when my red hat box starts up. My default run level is 5 but I want to make sure it works both in run level 3 & 5. ...
3
votes
1answer
463 views

difference between lam and paste

I don't get the difference between the program lam lam -- laminate files The lam utility copies the named files side by side onto the standard output. The n-th input lines from the ...
0
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4answers
1k views

Created a key using SSH keygen, can't see the folder using filezilla

I created a ssh key using: ssh-keygen -t dsa But when I use FileZilla (FTP) to my server, I can't see the .ssh folder or files. I even tried moving the id_dsa file to another folder but I still ...
0
votes
1answer
138 views

I did rm instead of mv, how can I reference my data folder again?

In this question: what did I do on my linux box, used the rm incorrectly I basically did a rm instead of a mv. Anyhow, it turns out the /data folder I deleted which was in my home folder is still ...
0
votes
6answers
124 views

what did I do on my linux box, used the rm incorrectly

What will this command do on unix: rm somefile ~/data I was trying to move somefile to the folder at home/data
1
vote
9answers
4k views

From within telnet (putty), can I download a file to my computer?

I generated a key for use with SSH (Subversion) on my Unix server, and I need to download the key. I tried to use an FTP program but the folders are hidden i.e. /.ssh/ Can someone download them ...
14
votes
9answers
4k views

Finding what's using all the space in *nix

Which sequence of commands will tell me which files are the largest starting from a particular directory, including all sub directories? I want to know where all the space went. Preferably just with ...
1
vote
2answers
718 views

How to find and then compare similar files in Dropbox folder?

I am using Dropbox, and I wind up with a number of files like: prefs (home's conflicted copy 2009-07-20).js What I would like to do is find all the "conflicted copy..." files and then compare each ...
14
votes
8answers
14k views

How can I prepend a line number and tab to each line of a text file?

How can I append a line number and tab to the beginning of each line of a text file?
29
votes
8answers
13k views

Rename a group of files with one command

If I have a group of files with a .htm extention, how can I rename them all to .html? mv *.htm *.html does not work.
10
votes
3answers
15k views

How can I use ssh to run a command on a remote Unix machine and exit before the command completes?

How can I use ssh to run a command on a Unix machine and exit before the command completes? For instance, if I type ssh localhost 'sleep 60 &' ssh hangs on my terminal until sleep completes, ...
2
votes
2answers
989 views

Run command on remote Unix machine without interactive session

How can I run a command on a remote Unix machine without starting a interactive session?
98
votes
10answers
56k views

How do I set up SSH so I don't have to type my password?

How do I set up SSH so I don't have to type my password when connecting to a host?
8
votes
3answers
3k views

Stop cron from emailing me

How can I stop cron from emailing me the results of jobs I schedule?
20
votes
2answers
7k views

Can the output of one command be piped to two other commands?

How can I pipe the output of one command to the input of two other commands simultaneously?
78
votes
9answers
37k views

How can I search the bash history and rerun a command?

Can I search history in bash and run the result?
1
vote
2answers
188 views

Change number of lines and columns in VT420?

I have a VT420 that displays 80 columns and 24 lines. I would like to use it with 132 columns and 48 lines.
1
vote
1answer
2k views

Is kill -STOP a temporary command?

I had paused 50 processes (background here) using kill -STOP and then that shell window crashed (probably a GUI issue - I had just asked the configuration for help on scrolling options), and that ...
9
votes
9answers
7k views

grep all .java files in a directory for a particular string

How would I search all .java files for a simple string (not a regex) in the current directory and all sub-directories on Mac OS X? I just want to print a list of file and directory names that match.
0
votes
1answer
145 views

Windows date reprensentation

I was debating about the 2038 bug on unix with a friend (the 32 bit timestamp bug). We were actually wondering on how windows store the dates itself ? I was thinking it was a simple DateTime but how ...
11
votes
9answers
6k views

“Detach” and “Reattach” xterms across X sessions?

Is there a way to save/detach an xterm (or another window), and reopen/load/reattach it on a different X session on the same machine ? What I'm trying to achieve is "move" running xterms between two ...
0
votes
1answer
156 views

Pause all but x CPU-intensive tasks

I've got about 50 folders of data to process, and I've got a ruby script that processes a folder's files (which folder it processes is based on a .yml configuration file). And a computer with four ...
17
votes
9answers
14k views

What's the difference between the commands “su -s” and “sudo -s”?

What is the difference between the two super user commands, su -s and sudo -s? They both give a shell with access to the superuser account.
12
votes
6answers
8k views

Full command text with unix ps

When we enter: ps -f ... the CMD column text doesn't show the full command. Any way to prevent this truncating? Seems like it's showing the first 80 characters. We are running a fairly ...
450
votes
7answers
288k views

How can I sort the output of 'ls' by last modified date?

How can I sort the output of ls by last modified date?
6
votes
4answers
458 views

Can my Linux box turn off the UPS after it shuts down?

I have an APC UPS with all my computer peripherals plugged into it. When I'm done using the computer, I'd like to be able to type "shutdown" or "init 0" and walk away from the machine, trusting that ...