A shell is software that lets users interact with the operating system, usually by typing at a command-line.

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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 ...
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4answers
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How to diff directories for different files, but not line-by-line

I want to see, recursively, files that are different in two directories. Diff can do this, but it shows me the line-by-line differences, which I don't want. Is there a tool that does this, or a way to ...
12
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4answers
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How can I use a bash like shell on windows

I use Linux and a Mac. I'll be teaching some command line stuff soon. What can I install on Windows to give me a terminal window most similar to a basic mac/linux bash shell. Would like to be able to ...
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4answers
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Why is the size of a directory always 4096 bytes in unix?

I am sure a directory file has much less information than 4096 bytes. I know the sector size is 4096 bytes. But normal files smaller than that do exist. Why does Unix reserve 4096 bytes for each ...
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4answers
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Terminal Vs. Shell [duplicate]

Possible Duplicate: What are the differences between shell , console & terminal? This probably sounds like a stupid question but I'm having a lot of trouble clearly differentiating ...
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8answers
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Growl Notifications for Shell Task Completion

(OSX Specific) I, like many others besides myself often find myself kicking off a process in the shell that takes a minute or two to complete (a large svn commit for example). During that time, I ...
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3answers
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Making Linux shell prompt show last return value

I'm currently on a Linux machine and the shell prompt is showing me the last return value and number of executed commands (picture included, with these numbers shown in purple). My own computer ...
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3answers
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How can I do Ctrl-Z and bg in one keypress to make process continue in background?

So I realized I follow this pattern of suspending the task and then letting it to continue too often with the Ctrl-Z bg sequence, I was wondering is there any way to compress that to single keypress? ...
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3answers
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Mac OSX: conventional places where binary files should live

I'm only vaguely familiar with Unix and the filesystem convention for Macs, so sorry if this is a dumb/easy question. I've downloaded an application that is a command-line application, and want to ...
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6answers
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Stop Windows 7 Explorer from automatically expanding folders

Windows 7 Explorer can be opened in any folder from the command line. But, it automatically expands (on the left nav panel) the Favorites, Desktop, and [Username] folders. This makes it hard to see ...
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1answer
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Why do we have login, non-login, interactive, and non-interactive bash shells?

So the bash man pages explain what login and interactive shells are: A login shell is one whose first character of argument zero is a -, or one started with the --login option. An ...
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5answers
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How to show the current Vi mode when using Vi keybindings in the shell?

I use the vi keybindings in my tcsh shell. Now, I don't know which vi mode I'm in (insert mode or command mode), which leads to a lot of frustration. Does anyone know of a way to show the current ...
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5answers
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Finding the definition of a bash function

I work in an environment that has a lot of legacy shell script magic lying around. One thing used heavy from the command line are bash functions that get sourced from some file included from some ...
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10answers
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Determine Linux distribution

I am trying to determine what flavor of linux server is running. I am not trying to determine the kernel version - but rater the distributor. gcc is installed, and in the version output, it says ...
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11answers
15k views

Is there any replacement for putty [closed]

Is there any nice looking terminal with more features and sexy looks than putty? I find it very boring.
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3answers
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What's the difference between /etc/bash.bashrc and ~/.bashrc? Which one should I use?

When should I use each of the two .bashrc files to set my aliases, prompt, etc?
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2answers
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How to set terminal size in Android adb shell?

When I connect to Android using "adb shell" and run certain commands such as "vim" or "mc", they are restricted to a "window" of 25x80 characters. Since I'm connecting from a desktop computer where ...
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2answers
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Unix: How to merge two directories

Say I have two folders with various content, foo and bar. How can I merge bar into foo so that: Files in foo that are not in bar are untouched. Files in bar that are not in foo are now in foo. Files ...
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2answers
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http get from the shell in Mac OS X

I'd like to download a link like: http://example.org/file.mp3 Now, I'm enough of a shell junkie to know what SCP does, but that's about where my geek-dom ends. So is there a shell program that lets ...
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3answers
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Bash shell: list all files of type .png or .PNG?

In a bash script, how can I say 'for all files of type .png or .PNG'? I'm trying : for i in (`ls *.PNG` && `ls *.png`) but getting a syntax error.
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2answers
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How do I host a mintty shell inside of Console2?

I like to use Console2 for my Windows shell work, where I usually make it open a cygwin bash prompt. I'd like to try out MinTTY (2), and want to host it within Console2 as well. If this is possible, ...
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5answers
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Is there a way to escape single-quotes in the shell?

E. g. I want to say perl -e 'print '"'"'Hello, world!'"'"', "\n";' Is there a less awkward way to do it, e. g. escaping single-quotes? Yes, I know that I can write perl -e 'print q[Hello, ...
11
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1answer
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Vim Ignores Aliases

If I map a command in vim using something like map <f4> :! pdflatex %<cr> Vim will ignore my alias for pdflatex (something like alias pdflatex='pdflatex --temp-dir=something'). Is it ...
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3answers
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TortoiseSVN overlay icons do not appear when installed by a different user account?

I've installed TortoiseSVN on my work Windows XP machine as the administrator. When I login in as a standard user my working copies do not display the overlay icons in Windows Explorer. I found this ...
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2answers
857 views

How to cut a file to a given size under Linux?

I want to shrink a file's size by brute-force, that is, I don't care about the rest, I just want to cut the file, say by half, and discard the rest. The first thing that comes to mind is Perl's ...
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4answers
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How do I rename files with spaces using the Linux shell?

I named a number of files with spaces in them, and I want to replace the space with "_". However, every time I write a command in the shell with the file name (eg "Spring 2011"), the shell doesn't ...
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9answers
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How do I copy file named starting with a dot?

I am trying to copy all files under directory A to directory B. All files under directory A are starting with dot, for example: A/.a A/.b A/.c which I found if I use: cp A/* B, always get error: ...
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5answers
464 views

What's the difference between filename and ./filename in Linux

What is the difference between filename and ./filename? Under what circumstances is one preferred to the other?
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8answers
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Windows Vista: How to execute a .exe program in the cmd “As Administrator”

Yes, that's it. I need to run a program .exe in the dos cmd line and it needs to run like when you right button and select "run as an administrator"
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8answers
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Mass renaming, *nix version

I was looking for a way to rename a huge number of similarly-named files, much like this one (a Windows-related question) except that I'm using *nix (Ubuntu and FreeBSD, separately). Just to sum up, ...
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4answers
590 views

Is it possible to print out the shell expansion?

I know there is a specific set of rules that shell expand the commands user typed. (let's talk about bash shell.) Is it possible to print out a command in the form after shell expansion? It seems to ...
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4answers
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Better way to do “echo $x | sed …” and “echo $x | grep …”

I often find this in scripts (and, I have to admit, write it myself): a=`echo $x | sed "s/foo/bar/"` or if echo $x | grep foo then ... fi Consider "foo" to include some regex stuff. I feel ...
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4answers
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Linux command to return number of bits (32 or 64)?

What is a Linux command that I can run to programmatically return either 32 or 64 to indicate whether the processor is a 32 bit or 64 bit processor?
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1answer
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why doesn't a bash while loop exit when piping to terminated subcommand?

Why doesn't the command below exit? Rather than exit, the loop runs indefinitely. While I discovered this behavior using a more complex setup, the simplest form of the command reduces to the ...
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1answer
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How do I make OS X set the terminal title back to the original title when coming back from ssh?

Starting on OS X, I ssh into foo (a Linux box). My terminal title changes to foo. I then ssh into bar (another Linux box). My terminal title changes to bar. I log out of bar. My terminal title ...
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2answers
287 views

How to move folder in unix using mv, only when target is on the same drive

I need to move a folder using unix mv command, but only if the target is in the same drive or the same filesystem. What would be the best approach?
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7answers
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Change directory using sudo

How to I change into a directory owned by root? If I do: sudo cd RootOwedDir I get: sudo cd: command not found If I su root I get: authentication failure, probably because I never really set up an ...
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3answers
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bash: colorized man page

Where do I have to take a look at in the system to colorize the man pages? The man pages are viewed with less, so I tried adding the following lines to my .bashrc to change the colors: (Which works ...
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2answers
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How to calculate a relative path from two absolute paths in Linux shell?

We have two paths. First one is directory, second either dir or file. /a/b/c and /a/d/e.txt Relative path from first path to second will be: ../../d/e.txt How to calculate that in Linux terminal? ...
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3answers
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How can I launch a file properties dialog from the command line?

It's simple programmatically with ShellExecute to specify the properties verb when instructing Windows to open a file, but can this be done from the command line or run box? Ideally I'd like to do ...
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votes
6answers
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What's the difference between the terms “Shell” and “Bash”?

What is the the difference between "Shell" and "Bash" and what do these terms mean? As far as I know, there is no difference. But I've seen many books about "Shell" and others about "Bash"! So in ...
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11answers
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how to `tail` the latest file in a directory

In shell, how can I tail the latest file created in a directory?
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4answers
8k views

Parallel shell loops

I want to process many files and since I've here a bunch of cores I want to do it in parallel: for i in *.myfiles; do do_something $i `derived_params $i` other_params; done I know of a Makefile ...
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12answers
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Best way to organise one's sh/bash/python/etc. scripts

What is the best way to organise the sh/bash/python scripts you collect and write on your system?
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2answers
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How can I found out if file is alias or symbolic link?

I'm working on a legacy system and I have a bunch of files that are referencing images that are located in other folders. lrwxrwxrwx 1 user nobody 56 Feb 10 2010 t100x100.jpg -> ...
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votes
1answer
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run or send a command to a tmux pane in a running tmux session

I want to write a shell script which will attach to a named tmux session, select a window (or pane) in that session and run a command in that selected window (or pane). How do I do this from a bash ...
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4answers
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Linux : To monitor a Service and restart if stopped?

Actually I'm not so sure whether i should use Shell Scripts, or if there some ways already. But whatever approach we use, i would like to keep a Service running all the time. Let's say iptables as an ...
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5answers
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gzip all files without deleting them

I need to gzip all files in a dir separately including all files in sub-directories without deleting the originals afterwards. So let's say I have index.html, I want to have at the end index.html.gzip ...
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2answers
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How can I prevent tmux exiting with Ctrl-d?

I use tmux on my server and recently I found to my cost that ctrl-d will exit tmux and lose all the session information, my intention was to simply end the ssh session but failed to notice I was still ...
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3answers
665 views

Figure out what non-symlink path would be?

On Linux, if I've cd'd around and am now in a directory, is there a way to figure out what the real path to that directory is if I had not used a symbolic link to get there? Consider: $ pwd ...