Generate specific, non-zero return code?

Question

I am working on some piece of python code that calls various linux tools (like ssh) for automation purposes. Right now I am looking into "return code" handling.

Thus: I am looking for a simple way to run some command that gives me a specific non-zero return code; something like

echo "this is a testcommand, that should return with rc=5"

for example. But of course, the above comes back with rc=0.

I know that I can call false, but this will always return with rc=1. I am looking for something that gives me an rc that I can control.

Edit: first answers suggest to exit; but the problem with that: exit is a bash function. So, when I try to run that from within a python script, I get "No such file or directory: exit".

So, I am actually looking for some "binary" tool that gives me that (obviously one can write some simple script to get that; I am just looking if there is something similar to false that is already shipped with any Linux/Unix).

How would you be running the command from Python? subprocess.Popen('exit 5', shell=True would work. — chepner
– chepner, Commented Sep 28, 2016 at 11:38

Ignacio Vazquez-Abrams · Accepted Answer · 2016-09-28 10:56:29Z

7

Run exit in a subshell.

$ (exit 5) ; echo $?
5

answered Sep 28, 2016 at 10:56

Ignacio Vazquez-Abrams

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3 Comments

GhostCat Over a year ago

That works nicely when I execute it directly within bash. But i need a command that python runs for me (like false). Any further thoughts are welcome.

Ignacio Vazquez-Abrams Over a year ago

In that case just invoke a shell in order to have it return the value. sh -c "exit 5"

GhostCat Over a year ago

Give or take some subtleties, in the cmd_str = "bash -c 'exit 5'" did the job! Thanks!

anishsane · Accepted Answer · 2016-09-28 11:43:10Z

3

I have this function defined in .bashrc:

return_errorcode () 
{ 
    return $1
}

So, I can directly use something like

$ return_errorcode 5
$ echo $?
5

Compared to (exit 5); echo $? option, this mechanism saves you a subshell.

answered Sep 28, 2016 at 11:43

anishsane

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Comments

P.... · Accepted Answer · 2016-09-28 10:58:32Z

2

This is not exactly what you are asking but custom rc can be achieved through exit command.

 echo "this is a test command, that should return with " ;exit 5
 echo $?
 5

answered Sep 28, 2016 at 10:58

P....

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