This C++ program is a CGI script, I have no desire to deal with exceptions. I&#39;d rather get a marginal performance boost and let the OS (Linux) handle cleanup after the process dies.

I am using the Standard C++ Library, and want any function to `die` like in Perl: **Whenever it throws an exception.** Without unwinding, *or running any further code* in my process.

How does -fno-exceptions work? If I have no catch at all in my code, and basically pretend like exceptions do no exist. but I **do** use std:: c++ library which **can** throw()?

Disabling C++ exceptions, how can I make any std:: throw() immediately terminate?

I want to write code like this:

    command=&quot;some command&quot;

    safeRunCommand $command

    safeRunCommand() {
       cmnd=$1

       $($cmnd)

       if [ $? != 0 ]; then
          printf &quot;Error when executing command: &#39;$command&#39;&quot;
          exit $ERROR_CODE
       fi
    }

But this code does not work the way I want. Where did I make the mistake?



Get the exit code for a command in Bash and KornShell (ksh)

What is the command in C# for exiting a console application?


What is the command to exit a console application in C#?

I would like to know how to I exit from Python without having an traceback dump on the output. 

I still want want to be able to return an error code but I do not want to display the traceback log.

I want to be able to exit using `exit(number)` without trace but in case of an Exception (not an exit) I want the trace.


How to exit from Python without traceback?

I am a noob in shell-scripting. I want to print a message and exit my script if a command fails. I&#39;ve tried:

    my_command &amp;&amp; (echo &#39;my_command failed; exit)

but it does not work. It keeps executing the instructions following this line in the script. I&#39;m using Ubuntu and bash.

How to exit if a command failed?

Is there something similar to pipefail for multiple commands, like a &#39;try&#39; statement but within bash. I would like to do something like this:

    echo &quot;trying stuff&quot;
    try {
        command1
        command2
        command3
    }

And at any point, if any command fails, drop out and echo out the error of that command. I don&#39;t want to have to do something like:

    command1
    if [ $? -ne 0 ]; then
        echo &quot;command1 borked it&quot;
    fi
    
    command2
    if [ $? -ne 0 ]; then
        echo &quot;command2 borked it&quot;
    fi

And so on... or anything like:

    pipefail -o
    command1 &quot;arg1&quot; &quot;arg2&quot; | command2 &quot;arg1&quot; &quot;arg2&quot; | command3

Because the arguments of each command I believe (correct me if I&#39;m wrong) will interfere with each other. These two methods seem horribly long-winded and nasty to me so I&#39;m here appealing for a more efficient method.

Checking Bash exit status of several commands efficiently

I have a published application in C#. Whenever I close the main form by clicking on the red exit button, the form closes but not the whole application. I found this out when I tried shutting down the computer and was subsequently bombarded by lots of child windows with `MessageBox` alerts I added.

I tried `Application.Exit` but it still calls all the child windows and alerts. I don&#39;t know how to use `Environment.Exit` and which integer to put into it either.

Also, whenever my forms call the `FormClosed` or `FormClosing` event, I close the application with a `this.Hide()` function; does that affect how my application is behaving?

How do I properly exit a C# application?

I&#39;m using Pry with my Rails application. I set `binding.pry` inside a loop in my model to try and debug a problem. For example:

    (1..100).each do |i|
      binding.pry
      puts i
    end

When I type `quit`, it goes to the next iteration and stops again. Is there a way to step out of the loop so I don&#39;t have to type `quit` 100 times?

Currently the only way I know how to get out of it is to use &lt;kbd&gt;CTRL&lt;/kbd&gt;+&lt;kbd&gt;C&lt;/kbd&gt; and restart the application.


How do I step out of a loop with Ruby Pry?

After entering `set -e` in an interactive bash shell, bash will exit immediately if any command exits with non-zero. How can I undo this effect?

How to undo the effect of &quot;set -e&quot; which makes bash exit immediately if any command fails?

Should I use `exit()` or just `return` statements in `main()`? Personally I favor the `return` statements because I feel it&#39;s like reading any other function and the flow control when I&#39;m reading the code is smooth (in my opinion). And even if I want to refactor the `main()` function, having `return` seems like a better choice than `exit()`.

Does `exit()` do anything special that `return` doesn&#39;t?

return statement vs exit() in main()

Lately, I&#39;ve been trying to learn C++ from [this website][1]. Unfortunately whenever I try to run one of the code samples, I see that program open for about a half second and then immediately close. Is there a way to stop the program from closing immediately so that I can see the fruits of my effort?

  [1]: http://www.cplusplus.com/doc/tutorial/


How to stop C++ console application from exiting immediately?

How can I exit the JavaScript script much like PHP&#39;s `exit` or `die`? I know it&#39;s not the best programming practice but I need to.


How to terminate the script in JavaScript?

I have an application where on the home page I have buttons for navigation through the application.

On that page I have a button &quot;EXIT&quot; which when clicked should take the user to the home screen on the phone where the application icon is.

How can I do that?

How to exit from the application and show the home screen?

In Java, What is the difference with or without `System.exit(0)` in following code? 

    public class TestExit
    {      
        public static void main(String[] args)
        { 
            System.out.println(&quot;hello world&quot;);
 
            System.exit(0);  // is it necessary? And when it must be called? 
        }      
    }

The [document][1] says: &quot;This method never returns normally.&quot; What does it mean? 


  [1]: 
http://docs.oracle.com/javase/7/docs/api/java/lang/System.html#exit(int)

When should we call System.exit in Java

I&#39;m writing a script in Bash to test some code. However, it seems silly to run the tests if compiling the code fails in the first place, in which case I&#39;ll just abort the tests.

Is there a way I can do this without wrapping the entire script inside of a while loop and using breaks? Something like a **dun dun dun** goto?


In a Bash script, how can I exit the entire script if a certain condition occurs?

I have a simple Python script that I want to stop executing if a condition is met.

For example:

    done = True
    if done:
        # quit/stop/exit
    else:
        # do other stuff

Essentially, I am looking for something that behaves equivalently to the &#39;return&#39; keyword in the body of a function which allows the flow of the code to exit the function and not execute the remaining code.




How do I abort the execution of a Python script?

Assume I&#39;m starting a `std::thread` and then `detach()` it, so the thread continues executing even though the `std::thread` that once represented it, goes out of scope.

Assume further that the program does not have a reliable protocol for joining the detached thread&lt;sup&gt;1&lt;/sup&gt;, so the detached thread still runs when `main()` exits.

I cannot find anything in the standard (more precisely, in the N3797 C++14 draft), which describes what should happen, neither 1.10 nor 30.3 contain pertinent wording.

&lt;sup&gt;1&lt;/sup&gt; Another, probably equivalent, question is: &quot;can a detached thread ever be joined again&quot;, because whatever protocol you&#39;re inventing to join, the signalling part would have to be done while the thread was still running, and the OS scheduler might decide to put the thread to sleep for an hour just after signalling was performed with no way for the receiving end to reliably detect that the thread actually finished.

If running out of `main()` with detached threads running is undefined behaviour, then _any_ use of `std::thread::detach()` is undefined behaviour unless the main thread never exits&lt;sup&gt;2&lt;/sup&gt;.

Thus, running out of `main()` with detached threads running must have _defined_ effects. The question is: _where_ (in the _C++ standard_, not POSIX, not OS docs, ...) are those effects defined.

&lt;sup&gt;2&lt;/sup&gt; A detached thread cannot be joined (in the sense of `std::thread::join()`). You _can_ wait for results from detached threads (e.g. via a future from `std::packaged_task`, or by a counting semaphore or a flag and a condition variable), but that doesn&#39;t guarantee that the _thread has finished executing_. Indeed, unless you put the signalling part into the destructor of the first automatic object of the thread, there _will_, in general, be code (destructors) that run _after_ the signalling code. If the OS schedules the main thread to consume the result and exit before the detached thread finishes running said destructors, what will^Wis defined to happen?

What happens to a detached thread when main() exits?

I&#39;m building a Shell Script that has a `if` function like this one:

    if jarsigner -verbose -keystore $keyst -keystore $pass $jar_file $kalias
    then
        echo $jar_file signed sucessfully
    else
        echo ERROR: Failed to sign $jar_file. Please recheck the variables
    fi
    
    ...

I want the execution of the script to finish after displaying the error message. How I can do this?

Exit a Script On Error

I&#39;ve been writing some shell script and I would find it useful if there was the ability to halt the execution of said shell script if any of the commands failed. See below for an example:

    #!/bin/bash

    cd some_dir

    ./configure --some-flags

    make

    make install

So in this case, if the script can&#39;t change to the indicated directory, then it would certainly not want to do a *./configure* afterwards if it fails.

Now I&#39;m well aware that I could have an if check for each command (which I think is a hopeless solution), but is there a global setting to make the script exit if one of the commands fails?




Automatic exit from Bash shell script on error

What are the differences between `die()` and `exit()` functions in PHP?

I think both have the same functionality, but I doubt there is something different in both... what is it?

What are the differences in die() and exit() in PHP?

How would you exit out of a function if a condition is true without killing the whole script, just return back to before you called the function.

Example

    # Start script
    Do scripty stuff here
    Ok now lets call FUNCT
    FUNCT
    Here is A to come back to
    
    function FUNCT {
      if [ blah is false ]; then
        exit the function and go up to A
      else
        keep running the function
      fi
    }

How to exit a function in bash

How should I quit a Qt Program, e.g when loading a data file, and discovered file corruption, and user need to quit this app or re-initiate data file?

  Should I:

 1. call `exit(EXIT_FAILURE)`
 1. call `QApplication::quit()`
 1. call `QCoreApplication::quit()`

And difference between (2) and (3)?

Correct way to quit a Qt program?

How can you have a function or something that will be executed before your program quits? I have a script that will be constantly running in the background, and I need it to save some data to a file before it exits. Is there a standard way of doing this?

Doing something before program exit

I have a Docker container running in a host of 1G RAM (there are also other containers running in the same host). The application in this Docker container will decode some images, which may consume memory a lot. 

From time to time, this container will exit. I doubt it is due to out of memory but not very sure. I need a method to find the root cause. So is there any way to know what happened for this container&#39;s death? 

 

How to know the reason why a docker container exits?

In C and C++, what is the difference between `exit()` and `abort()`? I am trying to end my program after an error (not an exception).

What is the difference between exit() and abort()?

I&#39;ve got myself into a muddle via an interactive rebase, and I now wish to abort it.  (i.e. go back to the point before I was dropped into interactive rebase mode, in my case via `git pull --rebase`.)  The way to do this seems to be via `git rebase --abort`, but this doesn&#39;t work:

    $ git rebase --abort
    error: Ref refs/heads/master is at 55b388c141b1485b1acd9e050dbeb0eb90ef2ee7 but
    expected b918ac16a33881ce00799bea63d9c23bf7022d67
    fatal: Cannot lock the ref &#39;refs/heads/master&#39;.
    Could not move back to refs/heads/master

How can I get out of interactive rebase mode, and clean up all references to it?  (`git reset --hard` succeeds, but doesn&#39;t drop me out of rebase mode.)

How to abort an interactive rebase if --abort doesn&#39;t work?

Could someone explain the key differences between `os.Exit()` and `panic()` and how they are used in practice in Go?

When to use os.Exit() and panic()?

I have a bunch of system calls in ruby such as the following and I want to check their exit codes simultaneously so that my script exits out if that command fails.

    system(&quot;VBoxManage createvm --name test1&quot;)
    system(&quot;ruby test.rb&quot;)

I want something like

`system(&quot;VBoxManage createvm --name test1&quot;, 0)` &lt;-- where the second parameter checks the exit code and confirms that that system call was successful, and if not, it&#39;ll raise an error or do something of that sort.

Is that possible at all?


I&#39;ve tried something along the lines of this and that didn&#39;t work either.

    system(&quot;ruby test.rb&quot;)
    system(&quot;echo $?&quot;)

or 

    `ruby test.rb`
    exit_code = `echo $?`
    if exit_code != 0
      raise &#39;Exit code is not zero&#39;
    end



ruby system command check exit code

I just moved over to the Visual Basic team here at work.

What is the equivalent keyword to `break` in Visual Basic, that is, to exit a loop early but not the method?


 Equivalent VB keyword for &#39;break&#39;

What is difference between return and exit statement in C programming when called from anywhere in a C program?

What is the difference between exit and return?

I am creating temporary files from a bash script. I am deleting them at the end of the processing, but since the script is running for quite a long time, if I kill it or simply CTRL-C during the run, the temp files are not deleted.  
Is there a way I can catch those events and clean-up the files before the execution ends?

Also, is there some kind of best practice for the naming and location of those temp files?  
I&#39;m currently not sure between using:

    TMP1=`mktemp -p /tmp`
    TMP2=`mktemp -p /tmp`
    ...

and

    TMP1=/tmp/`basename $0`1.$$
    TMP2=/tmp/`basename $0`2.$$
    ...

Or maybe is there some better solutions?
    


Removing created temp files in unexpected bash exit

What is the difference between the `return` and `exit` statement in Bash functions with respect to exit codes?

Difference between return and exit in Bash functions

I am trying to create a WPF application that takes command line arguments. If no arguments are given, the main window should pop up. In cases of some specific command line arguments, code should be run with no GUI and exit when finished. Any suggestions on how this should properly be done would be appreciated.

WPF Command Line

In Python, there are two similarly-named functions, `exit()` and `sys.exit()`. What&#39;s the difference and when should I use one over the other?

Difference between exit() and sys.exit() in Python

I have a console application that contains quite a lot of threads.  There are threads that monitor certain conditions and terminate the program if they are true.  This termination can happen at any time.

I need an event that can be triggered when the program is closing so that I can cleanup all of the other threads and close all file handles and connections properly.  I&#39;m not sure if there is one already built into the .NET framework, so I&#39;m asking before I write my own.

I was wondering if there was an event along the lines of:

    MyConsoleProgram.OnExit += CleanupBeforeExit;

Capture console exit C#

I have a program that does some data analysis and is a few hundred lines long.  

Very early on in the program, I want to do some quality control and if there is not enough data, I want the program to terminate and return to the R console. Otherwise, I want the rest of the code to execute.

I&#39;ve tried `break`,`browser`, and `quit` and none of them stop the execution of the rest of the program (and `quit` stops the execution as well as completely quitting R, which is not something I want to happen). My last resort is creating an `if-else` statement as below:

     if(n &lt; 500){}
     else{*insert rest of program here*}

but that seems like bad coding practice.  Am I missing something?

break/exit script

I was using the &quot;exit 1&quot; statement in my Bash functions to terminate the whole script and it worked fine:

    function func()
    {
       echo &quot;Goodbye&quot;
       exit 1
    }
    echo &quot;Function call will abort&quot;
    func
    echo &quot;This will never be printed&quot;

But then I realized that it doesn&#39;t do the work when called like:

    res=$(func)

I understand that I created a subshell and &quot;exit 1&quot; aborts that subshell and not the primary one....

But **is there a way to write a function which aborts the whole execution, no matter how it is called?** I just need to get the real return value (echoed by the function).





Is there a way to write a Bash function which aborts the whole execution, no matter how it is called?

What is the best way to exit/terminate a while loop in Java?


For example, my code is currently as follows:

    while(true){
        if(obj == null){

            // I need to exit here

        }
    }

How do I exit a while loop in Java?

I need to use `defer` to free allocations manually created using `C` library, but I also need to `os.Exit` with non 0 status at some point. The tricky part is that `os.Exit` skips any deferred instruction:

    package main
    
    import &quot;fmt&quot;
    import &quot;os&quot;
    
    func main() {
    
        // `defer`s will _not_ be run when using `os.Exit`, so
        // this `fmt.Println` will never be called.
        defer fmt.Println(&quot;!&quot;)
        // sometimes ones might use defer to do critical operations
        // like close a database, remove a lock or free memory
    
        // Exit with status code.
        os.Exit(3)
    }

Playground: http://play.golang.org/p/CDiAh9SXRM stolen from https://gobyexample.com/exit

So how to exit a go program honoring declared `defer` calls? Is there any alternative to `os.Exit`?

How to exit a go program honoring deferred calls?

Is it possible to exit on error, with a message, **without** using **if** statements?

    [[ $TRESHOLD =~ ^[0-9]+$ ]] || exit ERRCODE &quot;Threshold must be an integer value!&quot;

Of course the right side of `||` won&#39;t work, just to give you better idea of what I am trying to accomplish.

Actually, I don&#39;t even mind with which ERR code it&#39;s gonna exit, just to show the message.


**EDIT**

I know this will work, but how to suppress `numeric arg required` showing
after my custom message?


	[[ $TRESHOLD =~ ^[0-9]+$ ]] || exit &quot;Threshold must be an integer value!&quot;



exit with error message in bash (oneline)

Is there a way in Java to handle a received SIGTERM?

How to handle a SIGTERM

I have a question regarding launching new activities. It boils down to this.
I have 3 tabs on a view
 

    A) contains gMap activity
     B) camera activity
     C) some random text fields.

Requirement is that the application runs in Portrait mode. 

 All 3 tabs work as expected w/ the exception of the Camera Preview Surface (B). It is rotated 90 degrees. They only way to make it correct is to set the app to landscape which throws all my tabs around, and is pretty much unworkable.

 My solution is this : replace 

 my camera activity with a regular activity that is empty w/ the exception of 

    Intent i = new Intent(this,CameraActivity.class);
    	startActivity(i);

This launches my CameraActivity. And that works fine. I had to do a linear layout and include 3 images that look like real tabs, so I can try and mimic the operation of the tabs while rotating the screen to landscape and keep the visuals as portrait.
The user can click one of the images(buttons) to display the next tab. This is my issue. It should exit my &#39;camera activity&#39; returning to the &#39;blank activity&#39; in a tab, where it should be interpreted to click the desiered tab from my image. 

The main thing is, when it returns, it returns to a blank (black) page under a tab (because it is &#39;empty&#39;). How can I capture the return event back to the page that called the activity, and then see what action they performed? 

I can set an onclicklistener where I can respond to the fake tabs (images) being clicked to exit out of the camera activity. On exit, the tab should update so that is where you return. any Suggestions?

Thanks,

Android: Capturing the return of an activity

I can&#39;t find a recommended way to stop a function part way when a given condition is met. Should I use something like `exit` or `break`?

I am currently using this:

    if ( x &gt;= 10 ) { return; }  
    // other conditions;




Stopping a JavaScript function when a certain condition is met

What&#39;s the idiomatic way to exit a program with some error code?

The documentation for `Exit` says &quot;The program terminates immediately; deferred functions are not run.&quot;, and `log.Fatal` just calls `Exit`. For things that aren&#39;t heinous errors, terminating the program without running deferred functions seems extreme.

Am I supposed to pass around some state that indicate that there&#39;s been an error, and then call `Exit(1)` at some point where I know that I can exit safely, with all deferred functions having been run?

Exit with error code in go?

I am still pretty new to C# and am having a difficult time getting used to it compared to C/CPP. 

How do you exit a function on C# without exiting the program like this function would?

    if (textBox1.Text == &quot;&quot; || textBox1.Text == String.Empty || textBox1.TextLength == 0)
        textBox3.Text += &quot;[-] Listbox is Empty!!!!\r\n&quot;;
    System.Environment.Exit(0);

This will not allow return types and if left alone it will keep going on through the function unstopped. Which is undesirable.

How to Exit a Method without Exiting the Program?

The docs say that calling sys.exit() raises a SystemExit exception which can be caught in outer levels.  I have a situation in which I want to definitively and unquestionably exit from inside a test case, however the unittest module catches SystemExit and prevents the exit.  This is normally great, but the specific situation I am trying to handle is one where our test framework has detected that it is configured to point to a non-test database.  In this case I want to exit and prevent any further tests from being run.  Of course since unittest traps the SystemExit and continues happily on it&#39;s way, it is thwarting me.

The only option I have thought of so far is using ctypes or something similar to call   exit(3) directly but this seems like a pretty fugly hack for something that should be really simple.

Is there a way to prevent a SystemExit exception raised from sys.exit() from being caught?

I use &quot;source&quot; inside a bash script, as follows:


    #!/bin/bash
    source someneatscriptthatendsprematurely.sh

I would like to exit from the someneatscriptthatendsprematurely.sh script, without exiting from the main script.

Any help appreciated!

How do you return to a sourced bash script?

Is there a way to immediately stop execution of a SQL script in SQL server, like a &quot;break&quot; or &quot;exit&quot; command?

I have a script that does some validation and lookups before it starts doing inserts, and I want it to stop if any of the validations or lookups fail.

SQL Server - stop or break execution of a SQL script

I am looking for the R equivalent of linux/POSIX exit(n) which will halt the process with exit code n, signaling to a parent process that an error had occurred.  Does R have such a facility?

Make R exit with non-zero status code

I&#39;m currently launching a programme using `subprocess.Popen(cmd, shell=TRUE)`

I&#39;m fairly new to Python, but it &#39;feels&#39; like there ought to be some api that lets me do something similar to:

    subprocess.Popen(cmd, shell=TRUE,  postexec_fn=function_to_call_on_exit)

I am doing this so that `function_to_call_on_exit` can do something based on knowing that the cmd has exited (for example keeping count of the number of external processes currently running)

I assume that I could fairly trivially wrap subprocess in a class that combined threading with the `Popen.wait()` method, but as I&#39;ve not done threading in Python yet and it seems like this might be common enough for an API to exist, I thought I&#39;d try and find one first.

Thanks in advance :)

Python subprocess: callback when cmd exits

I&#39;ve been trying to figure out how the fork-exec mechanism is used inside Linux.  Everything was going on according to the plan until some web pages started to confuse me.

It is said that a child process should strictly use `_exit()` instead of a simple `exit()` or a normal return from `main()`. 

As I know, Linux shell fork-execs every one of the external commands; assuming what I said above is true, the conclusion is that none of these external commands nor any other execution happening inside the Linux shell can do normal return!

Wikipedia &amp; some other webpages claim we&#39;ve got to use `_exit()` just to prevent a child process causing deletion of parent&#39;s temporary files while a probable double flushing of stdio buffers may happen. though I understand the former, I have no clues how a double flushing of buffers could be harmful to a Linux system.

I&#39;ve spent my whole day on this...
Thanks for any clarification.

What is the difference between using _exit() &amp; exit() in a conventional Linux fork-exec?

What&#39;s the difference? Which is preferred, or when should I use each one respectively?

EXIT_FAILURE vs exit(1)?

I have a little console C# program like 

    Class Program 
    { 
        static void main(string args[]) 
        {
        }
    }

Now I want to do something after main() exit. I tried to write a deconstructor for Class Program, but it never get hit.

Does anybody know how to do it.

Thanks a lot

All Exit Solutions on Gang of Coders

Total of 53 Exit Solutions