The shell is unix's command-line interface. You can type commands in a shell interactively, or write scripts to automate tasks. Use this tag for questions applying to /bin/sh and most compatible shells (ash, bash, ksh, zsh, …).

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How to pass data outside process for zenity progress?

Usually this would be a question about how to pass data from a subprocess to a main process, but maybe zenity has some extra quirks so please focus on zenity. Example: #!/bin/sh ( echo "10" ; sleep ...
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5answers
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Formatting the output: Underlining

I wrote the following function in ksh that prints its first argument to the screen and underlines it with the appropriate ammount of - character: print_underlined () { word=$1 echo $word ...
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3answers
359 views

Numerically sorting files [duplicate]

Possible Duplicate: List files sorted numerically How can I sort this according to the number of last field? I tried with sort -t ' ' -k9,10n: -rw-r--r-- 1 root root 440 May 14 08:52 ...
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2answers
714 views

Weird zsh grep -P behaviour

I connect to server with PuTTY from Windows. I have a long yet not touched (I suppose) by hands of local admin config: $ cat /opt/jira/.subversion/config ... ### must be enabled, which is ...
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1answer
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Shell script filtering through jpg files attributes

I'm trying to find a way to filter through thousands of jpg files, and keep only the files with a certain attribute (such as the camera brand with which the picture was captured). How can I do so?
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How to remove the (1) from filenames using the find command

I recently converted all of my FLAC files to a lower sampling rate of 44.1 kHz and bit depth of 24 bits (because iPhone/iPod don't support anything above that) using XLD on my Mac OS 10.7 (Lion). ...
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3answers
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Why does bash variable expansion retain quotes?

> echo "hi" hi > VAR='echo "hi"' > $VAR "hi" Why is the output of the above commands different? A similar thing occurs with single quotes: > VAR="echo 'hi'" > $VAR > 'hi'
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2answers
825 views

pure shell complex substitution in variable

However it may be impossible, I hope I'm just bad man reader =) Is there any way to substitute text in variables on several patterns at time or even using back reference? For example, I have ...
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1answer
305 views

Why doesn't dzen2 work when invoked via at?

dzen2 is a notification utility of sorts. This command will make a notification that says "Hi" appear on the screen: echo Hi | dzen2 -p Debian's at is a utility that schedules events to occur in ...
3
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1answer
908 views

Searching a file & excluding lines with a specified string

I have a large log file that contains numerous lines of the same entry, lets call it "repeat-info". As an example here is what a portion of the log might look like: [Timestamp] repeat-info ...
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4answers
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Best method to collect a random sample from a collection of files

Suppose there is a directory holding 300 data files. I want to randomly select 200 of those files and move them into another directory. Is there a way to do that under Unix/Linux?
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1answer
615 views

KSH styling text based menu using STDERR

Is it possible to format the STDERR in order to have a better looking menu using the select command? I have a simple select select oChoice in $(<tempMenu.menu) ; do case "$oChoice" in ...
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4answers
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Difference between Login Shell and Non-Login Shell?

I understand the basic difference between an interactive shell and a non-interactive shell. But what exactly differentiates a login shell from a non-login shell? Can you give examples for uses of a ...
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3answers
516 views

“Grep-ing” from A to B in hexdump's output

Here is the situation: I have to find in the output from an hexdump the bytes between a string A and a string B. The structure of the hexdump is something like: -random bytes -A + useful bytes + B ...
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2answers
456 views

Detect pattern repetition in a file

I want to make sure a file follows the following pattern: ... ... ... foo ... foo_KO ... ... ... bar ... ... ... ... bar_KO ... The file is extremely long, so, in other words, I want to make sure ...
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4answers
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How can I save the last command to a file?

When I am running my analyses using the bash shell, I often want to save the commands I've used that gave me good results to a file in the same directory (my "LOGBOOK", as its called) so that I can ...
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3answers
2k views

Removing apostrophe from all file names

I tried to remove apostrophe from all files' names in the directory. for i in *; do mv $i `echo $i | tr -d "'"`; done After executing this command nothing is renamed. Do you know what's wrong ...
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1answer
112 views

Solaris “clean” group files (or for that matter any text file)

I am looking to find a way to script a cleaning operation on the /etc/group file on a large number of servers. Looking for users in a particular group more than once. i.e. somegroup::100000:userA, ...
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3answers
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Regarding separate a single file into multiple files according to line separation

Currently, I have a plain text file, A, such as lowest priority very high significance. outstanding very novel In this file, every line contains a sentence. I want to separate this file into ...
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2answers
16k views

Why do I get error 255 when returning -1

I'm new into C++ programming and I have a very basic question. I've noticed that when I return -1 in C++ program and then check the exit status, I get 255. Why is that? The code is the most basic: ...
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1answer
21k views

How do I execute a remote shell script over SSH and be prompted for passwords by commands that require it in that script?

I want to do something like this ssh user@remote-domain.com ./remote_script.sh Contents of remote_script.sh #!/bin/bash hg pull This example is much simpler than what I am actually doing. I know ...
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4answers
14k views

How to find the total number of occurrences of text and files with find command

I am trying to run the find command to find the total number of occurrences of a particular text string and also the number of files which has this text string. What I have right now is this command. ...
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2answers
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Why doesn't `echo abc^H` just print `ab`?

As I recall, ^H means Backspace. I generated it by pressing CTRL+V, CTRL+H. So the ^H should remove the last character, as it is the same as Backspace and it should act just as if I pressed Backspace ...
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3answers
660 views

Order of redirections

I don't quite understand how the computer reads this command. cat file1 file2 1> file.txt 2>&1 If I understand, 2>&1 simply redirect Standard Error to Standard Output. By that ...
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1answer
718 views

Escape text for further passing to zenity

I am going to show an error window using zenity: /usr/bin/zenity --error --text="my error message" The error text to pass is obtained as output from another application. This output may contain ...
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1answer
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How to format a curl command for a special task?

There is a search page in a form http://site.com/search.php and it sends a search query via POST request. I want to fetch this request via curl command line tool to inspect a POST request. The HTML ...
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2answers
233 views

Finding program name by wildcard pattern

I am trying to write a script that will attempt to find if a certain program is installed. Lets say that the program is called, myprog. The problem is that the program can be named in different ...
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1answer
2k views

Determine current shell name [duplicate]

Possible Duplicate: How to test what shell I am using in a terminal? How do I determine the current shell path or shell name? I only really need to distinguish sh and bash, however a ...
5
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1answer
173 views

find usage - command line vs script

I am seeing different results from the find command between being run manually on the command line vs run in a script. If I run the following on the command line: find . -name '*.txt' ! -name ...
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8answers
3k views

What is the utility of the : command in shell scripting, given that it explicitly does nothing?

In the answer to this question about comments in shell scripting, it is indicated that the : is a null command that explicitly does nothing (but is not to be used for comments). What would be the ...
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2answers
444 views

issues with GNU tail -f and combination of commands

$ tail -f /logs/filename.log | awk '!(/list)' I am able to run this command in GNU Linux flavour But when I written in a script it is not working. test.ksh: variable="/logs/filename.log | awk ...
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4answers
3k views

Recursively rename subdirectories that match a regex

I have a media server with a folder called Series. (/media/Expansion2/Series/) In it, I have (surprise!) TV series. These are just the show names, e.g., /media/Expansion2/Series/The Big Bang Theory/ ...
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4answers
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How do I grep for multiple patterns?

I want to find all lines in several files that match one of two patterns. I tried to find the patterns I'm looking for by typing grep (foo|bar) *.txt but the shell interprets the | as a pipe and ...
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4answers
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Renaming files works, but soft links point to the old names. How can I fix that?

For example, I'm renaming many files inside a tree like this: [bash]$ for file in `find . -name "*gsf*"`; do `mv $file ${file/gsf/msf}`; done That renames all the instances of "gsf" in file names ...
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3answers
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Using awk to process ls output with spaces in filenames/paths

All, I have a script in which I use find command to filter out all png files in a given folder and list them along with their size. I want the output in the following format: someFile.png => 1.2K ...
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4answers
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Change font in echo command

Is it possible to change the font attributes of the output of echo in either zsh or bash? What I would like is something akin to: echo -n "This is the font: normal " echo -n $font=italic "italic," ...
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5answers
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cd by just typing the directory's name?

I either had this somewhere 20 years ago or I dreamed about it. Basically: If if type blobblob I get blobblob: command not found Fair enough. I would like it so that when my shell gets those ...
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1answer
157 views

Load command parameters from upper level file

I've come across an interesting problem that I have not yet been able to solve satisfyingly. Consider a note taking command that takes two arguments: note $project $note That simply files the ...
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1answer
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Running shell commands in .sh file results to error

I have two following linux shell commands: echo 'CPU type and model' cat /proc/cpuinfo | head -5 | tail -1 When i run these commands directly in Terminal, i get this result truly: CPU type and ...
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4answers
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What is the difference between “&&” and “;” when chaining commands

What is the difference between the following methods of chaining commands? cmd1; cmd2 cmd1 && cmd2
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3answers
1k views

Which are the standard commands available in every Linux based distribution?

I would like to know which are the standard commands available in every Linux system. For example if you get a debian/ubuntu/redhat/suse/arch/slackware etc, you will always find there commands like: ...
2
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1answer
277 views

Delete repeated words between brackets inline

Our input looks something like 2012-04-17 [GBPGBP] 2012-04-13 [GBP GBP] 2012-04-13 [GBP] 2012-04-11 [GBPGBP] 2012-04-11 [GBP GBP] 2012-04-10 [GBPGBP] 2012-04-06 [GBP GBP GBP] 2012-04-17 ...
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3answers
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Change the color of the file name text

I am writing scripts to initialize and configure a large system with many components. Each component has its own log file. I would like to change the color of the component file name to red whenever ...
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2answers
690 views

Is there any simple way to change one line in a lot of files?

I'm trying to use PHP CodeSniffer, and here's the result: ----------------------------------------------------------------- A TOTAL OF 3008 ERROR(S) AND 380 WARNING(S) WERE FOUND IN 46 FILE(S) ...
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2answers
1k views

log remote X session from ssh (PuTTY)

I've googled alot about this and can't find a way to do this (or if it's even possible) I want to log a user on a remote machine in his X session (Gnome) from a ssh in a windows machine with PuTTY. ...
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1answer
1k views

Where does plink (from Putty package) search for remote commands?

I need to use plink (or something similar if you have something on mind) to get the output from Debian remote machine onto my Windows box. This works e.g. in this case : plink 192.168.1.5 "ls" > ...
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3answers
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Substituting strings in a very large file

I have a very long series of urls with no separating character, in the same format as below: http://example.comhttp://example.nethttp://example.orghttp://etc... I want each URL to be on a new line. ...
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4answers
2k views

Change password in headless mode

I am building a script to fully automate a VPS setup, and I need to change the root password. I would like to avoid typing it as the script is running through SSH. Is there a way to redirect an ...
4
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1answer
2k views

How to create a confirmation question in Linux?

I have a certain command (git push server-name) that has major consequences. How to require confirmation for this command only? It should ignore white space. The confirmation could be Enter 'yes i am ...
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4answers
7k views

symbolic link to a directory and relative path

I've created symlink with absolute path to the directory (Blink) and have for example following tree: $ ls -l /tmp/A total 0 lrwxrwxrwx 1 root root 6 Apr 3 12:27 Blink -> /tmp/B -rw-r--r-- 1 root ...