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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2
votes
1answer
43 views

Is there any way to check email sent success acknowledgement?

I need to send the generated CSV files on regular intervals using script. I am using UUENCODE and mailx for the same. But i need to know that is there any method/way to know that email sent ...
29
votes
6answers
2k views

When do you use brace expansion?

I understand what brace expansion is, but I don't know how best to use it. When do you use it? Please teach me some convenient and remarkable examples if you have your own tip.
1
vote
1answer
30 views

using script function rather than keyboard input

I'm writing a shell script to change a user's password. I tried to use the passwd command, but that command always asks for the old and new passwords to be typed; it won't accept them from my script. ...
1
vote
1answer
41 views

How to remove message when opening terminal/solve?

I am receiving the below message whenever I open the terminal. Repository u'ffmulticonverter_stable': Error parsing config: Error parsing "baseurl = u'ppa:ffmulticonverter/stable'": URL must be ...
37
votes
8answers
18k views

How to test what shell I am using in a terminal?

How to check what shell I am using in a terminal? What is the shell I am using in MacOS?
3
votes
1answer
77 views

How do I come by this pty and what can I do with it?

It seems that a simple shell redirect from /dev/ptmx gets me a new pseudo-terminal. $ ls /dev/pts; ls /dev/pts </dev/ptmx 0 1 2 ptmx 0 1 2 3 ptmx It disappears as soon as the process that ...
0
votes
1answer
32 views

unable to read the output to run the next command [closed]

When this script is executed I get the PID. Now I want to read the output "PID" and run the next command in this way: ps -ef | grep -i PID ps -ef | grep -i PID while read -r -u10 server port ...
2
votes
3answers
42 views

How to enter the condition to check 0 or more than 0 in case

I am trying to use case to run this function if [[ $input -gt 0 || $input -eq 0 ]]; Is it possible to put in case to test the input for greater than 0 or equal to 0, or even 0 and less than 0, in ...
5
votes
2answers
184 views

If any spawned child processes fail, kill all and exit

In my script I split up a data set into input_aa, input_ab, etc. Then, I run each through the same Python script, as such: # Execute program on each split file for part in input_*; do python3 ...
65
votes
12answers
24k views

Get exit status of process that's piped to another

I have two processes foo and bar, connected with a pipe: $ foo | bar bar always exits 0; I'm interested in the exit code of foo. Is there any way to get at it?
2
votes
0answers
46 views

“Restart” a process in the same terminal?

I put "restart" in quotes because the following question on SO illustrates what I'm trying to do: http://stackoverflow.com/questions/27957091/restarting-a-process-in-the-same-linux-terminal I'm ...
2
votes
3answers
56 views

Print file name extension using -exec in find

I am playing around with -exec flag of find command. I am trying to use the flag to print the extension name of files, using a fairly new Linux distribution release. Starting simple, this works: ...
1
vote
0answers
46 views

script needs to add another loop

script which runs netstat -tulpun | grep -i port_from_the_list & takes the output for running the next command I need to run 2 command on all the server mentioned in the list. server: Jan port: ...
63
votes
26answers
11k views

Quick directory navigation in the terminal

I would like to frequently switch between directories that are in totally unrelated paths, for example /Project/Warnest/docs/ and ~/Dropbox/Projects/ds/test/. But I don't want to type cd ...
2
votes
1answer
59 views

Can lightdm/gnome/compiz use bash instead of sh?

On my Ubuntu 12.04 logging in is handled by the lightdm which starts a gnome-session for the user which starts a compiz instance which then starts the applications the user clicks on. Somewhere in ...
36
votes
2answers
26k views

How do I use pushd and popd commands?

What are the practical uses of both pushd and popd when there is an advantage of using these two commands over cd and cd -? EDIT: I'm looking for some practical examples of uses for both of these ...
5
votes
2answers
152 views

Two-words argument in shell script

I have a problem with a shell script. It is supposed to read arguments: index, date, time1 (the beginning of the interval), time2 (the end of the interval). It should count how many times the ...
1
vote
3answers
120 views

How do I make an output for grep fail?

I am using if-else statement to search for keywords and displaying the results in the terminal, here's an example of my code. read finding if ["$finding" != "" ]; then grep $finding ...
1
vote
4answers
4k views

Removing a directory from PATH

I'm trying to compile wxWidgets using MingW, and I have cygwin in my path, which seems to conflict. So I would like to remove /d/Programme/cygwin/bin from the PATH variable and I wonder if there is ...
5
votes
2answers
57 views

Introduction of env --null

I have tried to extract environment variables in a Python process with help of env --null, which works even for environment variables containing newline character. But on some machines I have ...
1
vote
0answers
26 views

If I cancel when prompted for my Git password, I can no longer see anything I type, until I log back in [duplicate]

Everything still works (typing "exit", for instance, exits), but I can't see anything I type. There's not "funny characters", just nothing. Even re-running git and entering the password properly ...
1
vote
1answer
40 views

Why doesn't my function work with spaces? (cd, dirname) [duplicate]

I have had this function I use it very often and it works fine. Here it is: cdx () { cd `dirname $1` ; } However, this does not work with spaces. When I use it like this for example cdx ...
2
votes
1answer
30 views

Export path with space in directory name [duplicate]

I have a path "/third/party/city of las vegas" when cd the path I use "/third/party/city of las vegas". In .profile file I have exported the path to a variable as follows export ...
13
votes
6answers
1k views

Is there another simple way to append line to end of file other than `>>`?

Recently I'm echoing short sentences to a tree_hole file. I was using echo 'something' >> tree_hole to do this job. But I was always worried of what if I mis-input of > instead of >>, ...
17
votes
3answers
978 views

Is it safe to type another command into STDIN while the previous command is writing to STDOUT?

Perhaps this has been answered previously, I would welcome a link to another answer... If I execute a shell command (in a bash shell) like the following: make Then while the output from make is ...
1
vote
2answers
2k views

Busy box Read file line by line

There is no read applet comming with busy box. Is there any way to read a txt file line by line using busybox? What I have now is while read line do echo $line done < "$InputFile"
0
votes
2answers
36 views

Fetching data from server by FTP command

"Fetching data from server by FTP command" is not a problem .But if I like to fetch the today's file from the server, whose name is like (BACKUP20141210) and if it presents in a folder with previous ...
2
votes
3answers
24 views

Can RSH be told to use a specific shell

I am working with a c++ application which fires off a system command that launches a RSH sequence such as: rsh MACHINE \"setenv DISPLAY machine:0;setenv TESTVALUE1 'test';setenv scenTime 0;setenv ...
2
votes
0answers
37 views

How to get the mplayer's single-line playing progress info?

mplayer shows and refreshes a single-line playing progress when playing a media file. A sample result is: A: 17.2 (17.2) of 213.0 (03:33.0) 0.5% And I'm trying to grep this playing progress and ...
11
votes
3answers
16k views

Why I can't escape spaces on a bash script? [duplicate]

I'm trying to escape the space char for a path in Bash, but neither using a backslash or quotes works. .sh script: ROOT="/home/hogar/Documents/files/" FILE=${ROOT}"bdd.encrypted" ...
31
votes
7answers
2k views

Is test or [ or [[ more portable both between bash shells and between other shells?

I see I can do $ [ -w /home/durrantm ] && echo "writable" writable or $ test -w /home/durrantm && echo "writable" writable or $ [[ -w /home/durrantm ]] && echo ...
0
votes
1answer
30 views

How to autoremove with apt?

After uninstalling a package I used to do apt-get autoremove to remove other unused dependencies. I understand that apt (rather than apt-get) is the modern way to manage packages on the command-line ...
3
votes
2answers
68 views

How to use tee to capture STDOUT from a code block to a filename defined within the block?

I want to send STDOUT for a script block to a file which name is defined by a variable within the block. However, when I use tee, it seems the variable outside the block doesn't exist anymore. Without ...
1
vote
2answers
404 views

Can I put more than 1 condition in if?

Is it possible to put more than 1 condition in an if statement? if [ "$name" != "$blank" && "$age" == "$blank" ]; then Is it possible? If not how am I supposed to do that?
2
votes
2answers
68 views

How to use variables inside single quotes

I have an application which takes as an input attributes in double quotes embedded in single quotes. Take for example this right command: command -p 'cluster="cl1"' In order to automate it, I ...
5
votes
3answers
224 views

Save exit code for later

So I have a little script for running some tests. javac *.java && java -ea Test rm -f *.class Now the problem with this is that when I run the script ./test, it will return a success exit ...
2
votes
2answers
1k views

Is there a GUI debugger for shell scripts

Debugging bash scripts on command line is complicated. Is there a good GUI based debugger available for debugging bash scripts?
9
votes
5answers
773 views

How do I remove spaces from shell variables?

I have done the following at command line: $ text="name with space" $ echo $text name with space I am trying to use tr -d ' ' to remove the spaces and have a result of: namewithspace I've tried ...
0
votes
1answer
64 views

How do I put a checksum in a script?

I was (am) having trouble installing Eagle on my Linux (debian 8 jessie) computer. I was reading the installer script, when i noticed there is a checksum for the install script in the install script? ...
0
votes
2answers
49 views

Whats wrong with this case statement?

UPDATED: I am trying to do some color changes with my keyboard using apexctl depending on what time it is. But my case statement is giving me trouble. I want to compare the time when the script runs, ...
2
votes
0answers
55 views

Is there a difference between double quoting a variable or a whole line in echo

When you type, for example, echo Variable "$var" is not initialised. and echo "Variable $var is not initialised." the front end result is the exact same (as far as I know, at least). But I was ...
1
vote
1answer
31 views

rsync recursively with a certain depth of subfolders

I want to rsync a folder recursively but want subfolders included only to a certain depth. For example I would want a depth of 1,2,3 or 4 subfolders like this: source/ ├── subfolder 1 │   ├── ...
4
votes
3answers
413 views

Should I be using 'sudo' in scripts that I write?

I'm setting up a new machine (well actually, an Ubuntu VM) and am trying to write a script to setup a few common things that I use when doing this (Git, curl, vim + janus). So my script looks a bit ...
2
votes
2answers
112 views

Move specific files from multiple directories

I have got tons of directories with thousands files of various filetypes: dir |__ subdir | |__ file.foo | |__ file.bar | |__ file.txt | |__ (...) |__ (...) What is fast and ...
20
votes
2answers
15k views

How to remove a single line from history?

I'm working in Mac OSX, so I guess I'm using bash...? Sometimes I enter something that I don't want to be remembered in the history. How do I remove it?
3
votes
1answer
527 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 ...
0
votes
1answer
16 views

Is field splitting and filename expansion turn off in RHS of variable assignment portable?

In most POSIX compliant shell like bash. ksh, dash, mksh, pdksh, when variable assignment occur, field splitting and filename expansion (and brace expansion if the shell supports) are not performed in ...
1
vote
1answer
24 views

How do I transfer files over ssh and also change their permission on the remote server without having to log in twice

guy@home~% scp file.* guy@server.server.com:/users/guy/public_html/kool-stuff/ Ok so this transfers some files. Then I usually have to login in another terminal and do this in order to make them ...
3
votes
1answer
48 views
0
votes
1answer
25 views

How do i create a function to test if the input contains any character? [duplicate]

I have this set of example here to test if the user has keyed in any data after he presses enter. echo -n "Type a digit or a letter > " read character blank="" if [ "$character" != "$blank"]; ...