Shell
The term 'shell' refers to a general class of text-based interactive command interpreters most often associated with the Unix & Linux operating systems. For questions about shell scripting, please use a more specific tag such as 'bash', 'powershell' or 'ksh'. Without a specific tag, a portable (POSIX-compliant) solution should be assumed, though using 'posix' in addition or 'sh' instead is preferable.
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How do I test if a variable is a number in Bash?
I just can't figure out how do I make sure an argument passed to my script is a number or not. All I wan
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When do we need curly braces around shell variables?
In shell scripts, when do we use {} when expanding variables? For example, I have seen the following: var=10
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How to 'grep' a continuous stream?
Is that possible to use grep on a continuous stream? What I mean is sort of a tail -f <file> command, b
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Extract substring in Bash
Given a filename in the form someletters_12345_moreleters.ext, I want to extract the 5 digits and put them int
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Use grep --exclude/--include syntax to not grep through certain files
I'm looking for the string foo= in text files in a directory tree. It's on a common Linux machine, I
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How do I pause my shell script for a second before continuing?
I have only found how to wait for user input. However, I only want to pause so that my while true doesn't
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Add line break to 'git commit -m' from the command line
I am using Git from the command line and am trying to add a line break to the commit message (using git commit
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16
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Count number of lines in a git repository
How would I count the total number of lines present in all the files in a git repository? git ls-files gives
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What does set -e mean in a bash script?
I'm studying the content of this preinst file that the script executes before that package is unpacked fr
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How to call one shell script from another shell script?
I have two shell scripts, a.sh and b.sh. How can I call b.sh from within the shell script a.sh?
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Assigning default values to shell variables with a single command in bash
I have a whole bunch of tests on variables in a bash (3.00) shell script where if the variable is not set, the
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28
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Shell command to tar directory excluding certain files/folders
Is there a simple shell command/script that supports excluding certain files/folders from being archived? I h
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Get current directory name (without full path) in a Bash script
How would I get just the current working directory name in a bash script, or even better, just a terminal comm
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Shell command to sum integers, one per line?
I am looking for a command that will accept (as input) multiple lines of text, each line containing a single i
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How do I put an already-running process under nohup?
I have a process that is already running for a long time and don't want to end it. How do I put it under
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Replace one substring for another string in shell script
I have "I love Suzi and Marry" and I want to change "Suzi" to "Sara". #!/bin/bash firstString="I love Suzi an
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14
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How to echo shell commands as they are executed
In a shell script, how do I echo all shell commands called and expand any variable names? For example, given
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Defining a variable with or without export
What is export for? What is the difference between: export name=value and name=value
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How to reload .bash_profile from the command line?
How can I reload .bash_profile from the command line? I can get the shell to recognize changes to .bas
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How to call shell commands from Ruby
How do I call shell commands from inside of a Ruby program? How do I then get output from these commands back