It&#39;s an argument to `quit()`.  See `?quit`.

_Arguments_:

    status: the (numerical) error status to be returned to the operating
            system, where relevant.  Conventionally ‘0’ indicates
            successful completion.

_Details_:

     Some error statuses are used by R itself.  The default error
     handler for non-interactive use effectively calls ‘q(&quot;no&quot;, 1,
     FALSE)’ and returns error code 1.  Error status 2 is used for R
     ‘suicide’, that is a catastrophic failure, and other small numbers
     are used by specific ports for initialization failures.  It is
     recommended that users choose statuses of 10 or more.

    quit(status=1)

Replace `1` by whatever exit code you need.



What&#39;s the recommended location for SQL, DDL, ... scripts in [the Maven standard directory structure][1]?

I bet almost every web project uses a DB and some kind of SQL scripts that need to be stored somewhere, so what would probably be the &quot;best&quot; place where to keep these files?

Please advise.

  [1]: http://maven.apache.org/guides/introduction/introduction-to-the-standard-directory-layout.html

What&#39;s the recommended location for SQL (DDL) scripts?

I would like an explanation for the values used with the .cfi_def_cfa_offset directives in assembly generated by GCC. I know vaguely that the .cfi directives are involved in call frames and stack unwinding, but I would like a more detailed explanation of why, for example, the values 16 and 8 are used in the assembly outputted by GCC in compiling the following C program on my 64-bit Ubuntu machine.

The C program:

    #include &lt;stdio.h&gt;
    
    int main(int argc, char** argv)
    {
            printf(&quot;%d&quot;, 0);
            return 0;
    }

I invoked GCC on the source file test.c as follows: `gcc -S -O3 test.c`. I know that -O3 enables nonstandard optimization, but I wanted to limit the size of the generated assembly for the sake of brevity.

The generated assembly:


            .file   &quot;test.c&quot;
            .section        .rodata.str1.1,&quot;aMS&quot;,@progbits,1
    .LC0:
            .string &quot;%d&quot;
            .text
            .p2align 4,,15
    .globl main
            .type   main, @function
    main:
    .LFB22:
            .cfi_startproc
            subq    $8, %rsp
            .cfi_def_cfa_offset 16
            xorl    %edx, %edx
            movl    $.LC0, %esi
            movl    $1, %edi
            xorl    %eax, %eax
            call    __printf_chk
            xorl    %eax, %eax
            addq    $8, %rsp
            .cfi_def_cfa_offset 8
            ret
                .cfi_endproc
    .LFE22:
            .size   main, .-main
            .ident  &quot;GCC: (Ubuntu/Linaro 4.5.2-8ubuntu4) 4.5.2&quot;
            .section        .note.GNU-stack,&quot;&quot;,@progbits

Why are the values 16 and 8 used for the .cfi_def_cfa_offset directives in the generated assembly? Also, why is the number 22 used for the local function begin and function end labels?

GAS: Explanation of .cfi_def_cfa_offset

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

<p>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?</p>


I have an object from `ggplot2`, say `myPlot`, how can I identify the ranges for the x and y axes?

It doesn&#39;t seem to be a simple multiple of the data values&#39; range, because one can rescale plots, modify axes&#39; ranges, and so on.  `findFn` (from `sos`) and Google don&#39;t seem to be turning up relevant results, other than how to set the axes&#39; ranges.

How can I extract plot axes&#39; ranges for a ggplot2 object?

I have a huge vector which has a couple of `NA` values, and I&#39;m trying to find the max value in that vector (the vector is all numbers), but I can&#39;t do this because of the `NA` values.

How can I remove the `NA` values so that I can compute the max?


Remove NA values from a vector

I am trying to plot two variables where N=700K. The problem is that there is too much overlap, so that the plot becomes mostly a solid block of black. Is there any way of having a grayscale &quot;cloud&quot; where the darkness of the plot is a function of the number of points in an region? In other words, instead of showing individual points, I want the plot to be a &quot;cloud&quot;, with the more the number of points in a region, the darker that region.

Scatterplot with too many points

### Problem
I would like to test if an element of a list exists, here is an example

    foo &lt;- list(a=1)
    exists(&#39;foo&#39;) 
    TRUE   #foo does exist
    exists(&#39;foo$a&#39;) 
    FALSE  #suggests that foo$a does not exist
    foo$a
    [1] 1  #but it does exist

In this example, I know that `foo$a` exists, but the test returns `FALSE`. 

I looked in `?exists` and have found that `with(foo, exists(&#39;a&#39;)` returns `TRUE`, but do not understand why `exists(&#39;foo$a&#39;)` returns `FALSE`. 

### Questions

*  Why does `exists(&#39;foo$a&#39;)` return `FALSE`?
* Is use of `with(...)` the preferred  approach?

How to test if list element exists?

I would like to do some 2-dimensional walks using strings of characters by assigning different values to each character.  I was planning to &#39;pop&#39; the first character of a string, use it, and repeat for the rest of the string.

How can I achieve something like this?

    x &lt;- &#39;hello stackoverflow&#39;

I&#39;d like to be able to do something like this:

    a &lt;- x.pop[1]
    
    print(a)
    
    &#39;h&#39;
    print(x)

    &#39;ello stackoverflow&#39;

Getting and removing the first character of a string

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&#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?

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?

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)

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).





Content Type	Original Author	Original Content on Stackoverflow
Question	Setjmp	View Question on Stackoverflow
Solution 1 - R	Joshua Ulrich	View Answer on Stackoverflow
Solution 2 - R	ligand	View Answer on Stackoverflow

Make R exit with non-zero status code

R Problem Overview

R Solutions

Solution 1 - R

Solution 2 - R

GAS: Explanation of .cfi_def_cfa_offset

What's the recommended location for SQL (DDL) scripts?

Attributions