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Where to find the last command run in Bash?
The DEBUG trap lets you execute a command right before any simple command execution. A string version of the command to execute (with words separated by spaces) is available in the BASH_COMMAND variable. Note that previous_command will change every time you run a command, so save it to a variable in order to use it.
How to store a command in a variable in a shell?
#Or count of installed tune0 interfaces. Its is not necessary to store commands in variables even as you need to use it later. just execute it as per normal. If you store in variable, you would need some kind of eval statement or invoke some unnecessary shell process to “execute your variable”. Highly active question.
When to quote a variable in Bash stack?
Quote variables if those contain spaces. and it should be good. which would assign the line read to an array line. Otherwise bash interprets the whole string as the name of the command. Thanks for contributing an answer to Stack Overflow!
Why is the bar never printed in Bash?
After reading the answer from Gilles, I decided to see if the $BASH_COMMAND var was also available (and the desired value) in an EXIT trap – and it is! bar is never printed because set -e causes bash to exit the script when a command fails and the false command always fails (by definition).
Is there racecondition between last error and last command?
There is a racecondition between the last command ($_) and last error ( $?) variables. If you try to store one of them in an own variable, both encountered new values already because of the set command. Actually, last command hasn’t got any value at all in this case.
How to get the error message from Bash?
The line: e=$ (“$@” 2>&1 >&6) first directs stderr to stdout, which in the context of $ (..) is the output we’re capturing. Then stdout is directed to where it originally went when we started the function. Thanks for contributing an answer to Unix & Linux Stack Exchange!
How to print the last line of a script in Java?
I was able to achieve this by using set -x in the main script (which makes the script print out every command that is executed) and writing a wrapper script which just shows the last line of output generated by set -x.