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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5
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1answer
191 views

Grep for many arguments [duplicate]

Possible Duplicate: Grep command, to remove lines containing a specified word How do I grep for more than one words in one grep command. For example: cat file.txt | grep -v 'word1' | grep ...
1
vote
2answers
470 views

Unix Commands are not working

New to Unix, I recently tried to add a $PATH variable in Unix in order to debug my android sdk. I looked up online the directions and tried to follow them as thoroughly as possible. What ended up ...
3
votes
3answers
461 views

Mac- or Unix-compatible utility to compute and compare LAME MusicCRC in MP3s?

The LAME encoder stores a CRC16 checksum of the audio stream in the header of every MP3 it encodes. The 'actual' audio checksum can then be computed and compared to the original value at a later date ...
6
votes
2answers
1k views

How could a directory transform into a Unix file?

I have an NTFS hard drive which I've been reading/writing to on my iMac using NTFS-3G / Tuxera. The reason that it's NTFS formatted is because it came out of my old PC. Its singular function is the ...
1
vote
2answers
922 views

How to find the last match of a string in a bunch of files

I have a bunch of files, I'd like to find the last match of a string in each of them. grep text *.file gives me all the matches not the last ones. ls *.file | xargs grep text | tail -n 1 gives me ...
8
votes
1answer
11k views

What do the “ALL”s in the line “ %admin ALL=(ALL) ALL ” in Ubuntu's /etc/sudoers file stand for?

What does each ALL mean? I understand that the whole line indicates that the admin group members get admininstartive privileges, but would like to know more info about the position of the ALLS and if ...
0
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0answers
245 views

Copy read-only Unix files

My teacher created a subdirectory that has a bunch of very lengthy .pl files he wants us to use to test our code on. I usually just xfer any files I need through WinSCP, but I don't have permissions ...
2
votes
1answer
213 views

Unix User Group or Sudo/Su

I am in a situation where I have to chose between unix user groups or sudo to tackle an issue. To give some background, A Linux app is installed as user X. The installation copies some scripts and ...
1
vote
1answer
708 views

How to avoid duplicates when copying files that have been renamed at the destination

I have to get pictures from a folder – with subfolders which are updated automatically – with their extensions. These files have to be copied in a folder where a website based on PHP will edit them ...
5
votes
2answers
3k views

List directories containing files that match a regular expression

I would like to set up a simple filtering system on my FreeBSD server that allows me to create arbitrary "views" of directories. For instance, I'd like to be able to list all directories that match ...
2
votes
2answers
178 views

Debian - LAMP Install

I am installing a LAMP install on Debian GNU/Linux and have been asked to enter the following command sudo touch /var/www/info.php I was just wondering if anyone could explain what it does. ...
1
vote
4answers
157 views

How do I get the start and end timestamps of a command?

I have a tool that outputs to standard output every so often, without loss of generality, let's say that the sequence goes: mysystem$ ./runme Starting Done mysystem$ Now 'runme' takes a while to ...
1
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3answers
3k views

Copy files from remote Unix machine to windows

I have a remote Unix machine which doesnt have SMB installed and I cannot install it. However there are some files located on that server that I need on a windows machine. What I need is a way to ...
1
vote
2answers
53 views

What's appropriate hardware for getting started with UNIX network programming? [closed]

I'm interested in learning more about UNIX networking (socket programming etc). I prefer to use FreeBSD. What's appropriate computer hardware to purchase and get started on? I know this is a basic ...
7
votes
3answers
10k views

How do the '-s', '-t', and '-c' options of the tr command work in Unix?

I am confused regarding the way -s, -t, and -c options work in the tr command. When I do echo I am a good boy | tr good bad I get the output: I am a bddd bdy This is quite understandable, since ...
0
votes
2answers
929 views

How can I copy a file from a Unix server?

I have a bunch of files with the extension .dot on a unix server. These files will need to be saved into either a flash drive or windows hard drive. I am not very familiar with unix, and thus do not ...
4
votes
1answer
427 views

Why does Windows have a Unix-style etc/hosts? [closed]

Why does Windows have %systemroot%/system32/drivers/etc/hosts, as opposed to something more "Windowsy"? It feels like a relic from the BSD derivative Windows got some bits from eons ago. Is this ...
0
votes
4answers
959 views

When to use the 'tail -f' command?

I've come across the command line "tail -f log/[environment_name]" but, unfortunately, I've got no idea on how to use it and how it can do some good for me? Can anyone please shed some light on me on ...
1
vote
1answer
99 views

Ignoring path while archiving with TAR

I have a file that contain list of files I want to archive with tar. Let's call it mylist.txt It contains: /path1/path2/file1.txt /path1/path2/file3.txt ... /path1/path2/file10.txt What I want to ...
2
votes
0answers
596 views

How do I install LLVM 2.9 on Mac OS X Lion?

I need LLVM (2.9 specifically), but I can't figure out how to follow the installation instructions. Could someone kindly provide the step by step console commands for building/installing LLVM in the ...
0
votes
2answers
1k views

How to use Grep in Unix command line?

I want grep all lines containing words that start with "H" and end with "d". How would i do that? I found that grep ^H will give me the H for everyline.
0
votes
1answer
771 views

Update IP address to hostname mapping for currently logged in session

I'm logged into a Linux box but I do not have root access to update the /etc/hosts file. I am connecting to a remote server via its IP address but I would like to connect via hostname instead. Is it ...
2
votes
3answers
731 views

Really annoying keyboard screw up when entering sqlplus

Often when using bash I am used to using the keys ^A and ^E to go to the beginning and end of line, and the arrow keys to move from character to character without erasing. Every now and then, I ...
0
votes
1answer
630 views

Unable to use PSSH on Ubuntu

Hi I just installed PSSH on my Ubuntu machine and Iä'm trying to use it to execute commands across multiple machines but I keep getting errors. Here's some sample output to show what's going on. ...
1
vote
1answer
2k views

how do I compress all files within a folder on Unix?

I've been unable to compress the contents of a folder on Unix, note that I don't want to compress the directory itself but the contents inside. so far.. to compresss the files I use: compress ...
1
vote
1answer
71 views

Are rights 7110 equivalent to --S--S--s?

Are rights 7110 equivalent to --S--S--s? I mean the rights for Unix' chmod command.
0
votes
1answer
63 views

Where should I download new install files to in a Linux system?

Say I'm installing Redis. Where should I download the Redis files to? I'm guessing that doing it in my home directory isn't a good idea, just because it'll get messy with downloaded files over ...
11
votes
3answers
11k views

What does kill -3 mean?

I know kill -9 mean, but anyone can explain what does kill -3 mean? Any special signal it sends out?
8
votes
1answer
9k views

What's a good way to install “build essentials” (all common useful commands) on a blank EC2 Linux server?

I want to get some "build essentials" (like gcc, make, etc.) on an empty micro Linux box. Seems inefficient to spend my time trying to try installing one thing, then realize I need gcc, then realize ...
13
votes
4answers
4k views

What is the unix command to find out what executable file corresponds to a given command?

For example, if passed ls as input it should tell me that /bin/ls will run if run ls on the command-line.
2
votes
4answers
11k views

How do I set up the Unix 'mail' command?

I've had a look on Google and the man pages for mail, but I can't figure out how to set it up. All I want to do is set up my email address so that I can send email via the terminal. How do I do that?
0
votes
2answers
865 views

How can I create hard links in OSX?

What I want is to have multiple copies of the same file, and whenever I edit one of them, they all get updated. I thought Hard Links would solve my problem. So, I used the command ln as described in ...
2
votes
2answers
502 views

Is SSH history local or its server side?

I use Putty to access my dedicated servers trough SSH. When i click up arrow couple times i can see commands that i put in yesterday or at previous session. Do they stay locally or on server side? How ...
0
votes
1answer
537 views

Telnet error when connecting from Windows to Unix

When I try to connect through telnet from a Windows system to Unix, I am not able to connect. I am getting this log error. Is this related to a firewall issue, or anything I need to mention in the ...
3
votes
6answers
10k views

Is it possible to run a program through FTP prompt?

I'm relatively new to Unix or shell scripting (a total novice to speak the truth), here is the deal: I have BI software that runs on a remote UNIX server. Through SAS client on Windows i run some ...
4
votes
1answer
9k views

Grep command, to remove lines containing a specified word

I want to use grep in the following way: grep -v "END","EXPDTA" 1bmz_model1.pdb > 1bmz_model.pdb I want the grep command to remove the lines which contain the words "END" and "EXPDTA", but all i ...
2
votes
1answer
155 views

When I use sudo to run a command, aren't the environment variables visible?

$cat test export var=value $source ./test $cat print.sh echo $var $chmod +x print.sh $echo $var value $sudo ./print.sh I get nothing. I was expecting to see value. What is going on?
2
votes
1answer
549 views

How do I copy an egg from one python installation to another?

My server has Python 2.6 installed by default. I don't dare mess with the defaults, so I've installed Python 2.7 and Python 3.2 in separate locations and switch between them using bash alias as I need ...
0
votes
3answers
320 views

Location of files on Unix whose file names and contents each match a regular expression

I want to search for file names with a regular expression, and grep it using regex. I tried this: find . -name co_on*eruo* | xargs grep '0LF2C Comdty(.*)20111022(.*)' But it doesn't work. What am ...
1
vote
2answers
393 views

Did gzip destroy my log file?

I had a rather big log file. So I thought I'd gzip it before transferring it to my pc. I did gzip bla.log which gave me a tiny bla.log.gz When I extract it using gunzip bla.log.gz I get back ...
2
votes
8answers
153 views

How do I remove similar instances of lines using Unix commands?

I have a file that contains lines that look like the following: 14|geauxtigers|90 14|geauxtigers|null I want to remove all instances in the file with the null as the last term. Is there a way to do ...
2
votes
5answers
450 views

Multiple-command alias enters bash shell but fails to navigate to path

I have this alias defined to run bash then navigate to a certain folder but when I run it, it only runs bash and stays in the current path/directory/folder. I've defined them in two different ways in ...
1
vote
2answers
1k views

JAVA main class not found when using Apple auto-ingest tool

I am trying to setup a cronjob to download my daily and weekly reports from iTunes Connect. I have downloaded Apple's Autoingestion.class and I have made the following shell script to download the ...
3
votes
2answers
420 views

Is there something like the unix command “top” for CUDA?

More generally, how can you check the current status of your GPU? (current number of threads running, memory state, and so on). (I'm using linux, so Windows-only solutions, while interesting, won't ...
0
votes
1answer
291 views

Can't remove phpmyadmin because of file lock

I interrupt my remote-session during the installation of myphpadmin. Now I want to remove and reinstall it. Now suddenly when I type in sudo apt-get remove phpmyadmin the following error message ...
0
votes
4answers
221 views

How to split a long hex string

I've a long hex string 00121eafc5800020 ... etc. Is there an easy way I can split these with a space per hex coded byte so I get 00 12 1e af c5 80 00 20 in vim (or another easily accessible tool)
3
votes
4answers
311 views

How do I recall common bash command sets (i.e. “find”, “xargs”, & “grep” to find text in file)?

To customize my bash user experience, is there a way to use .bashrc to recall common command sets. For example I found this set of commands to find a search string in text files, find /directory ...
0
votes
3answers
83 views

Is there any file I can read in unix which contains the time

Is there any file in unix based system which I can read, to get the same value that time() in php would return?
1
vote
1answer
106 views

How to know the version of RPM during installation

I have created a script for deployment using YUM and RPM. During the pre script, is it possible to know whats the version of the rpm I am deploying. I want to create a backup file with the version ...
0
votes
2answers
479 views

How to foreground a job from another session

As root, is there a way to foreground (fg) a job within a root session that is in the foreground of another root session? If the job in the other session has to be put in the background (using bg) ...