How to print ( with printf ) complex number? For example, if I have this code:

    #include &lt;stdio.h&gt;
    #include &lt;complex.h&gt;
    int main(void)
    {
        double complex dc1 = 3 + 2*I;
        double complex dc2 = 4 + 5*I;
        double complex result;
    
        result = dc1 + dc2;
        printf(&quot; ??? \n&quot;, result);
        
        return 0;
    }
..what conversion specifiers ( or something else ) should I use instead &quot;???&quot;

C complex number and printf

How can I mark a test as an expected failure in JUnit 4?

In this case I want to continue to run this test until something is patched upstream. Ignoring the test goes a little too far, as then I might forget about it. I may be able to add an `@expected` annotation and catch the exception thrown by `assertThat`, but that also seems to lie about the expected behavior.

Here&#39;s what my current test looks like:

    @Test
	public void unmarshalledDocumentHasExpectedValue() 
	{
		doc = unmarshaller.unmarshal(getResourceAsStream(&quot;mydoc.xml&quot;));
		final ST title = doc.getTitle();
		assertThat(doc.getTitle().toStringContent(), equalTo(&quot;Expected&quot;));
	}

That assert should succeed, but because of an upstream bug it doesn&#39;t. Yet, that test is correct; it should succeed.  Virtually all the alternatives that I&#39;ve found are misleading.  Right now I think `@Ignore(&quot;This test should pass once fixed upstream&quot;)` is my best bet, but I still have to remember to come back to it. I&#39;d prefer that the test run.

In Python I can use the [expectedFailure][1] decorator:

    class ExpectedFailureTestCase(unittest.TestCase):
        @unittest.expectedFailure
        def test_fail(self):
            self.assertEqual(1, 0, &quot;broken&quot;)

With Qt&#39;s [QTestLib][2] in C++, you can use [QEXPECT_FAIL][3]:

    QEXPECT_FAIL(&quot;&quot;, &quot;Will be fixed next version&quot;, Continue);
    QCOMPARE(i, 42);

In both cases above, the unit test runs which is what I&#39;m hoping to have happen. Am I missing something in JUnit?

  [1]: http://docs.python.org/dev/library/unittest.html#unittest.expectedFailure
  [2]: https://doc.qt.io/qt-4.8/qtestlib-manual.html#qtestlib
  [3]: https://doc.qt.io/qt-5/qtest.html#QEXPECT_FAIL

Mark unit test as an expected failure in JUnit

I need to add a public key to `ssh-agent` but I&#39;m getting the following error

&gt; Could not open a connection to your authentication agent.

I&#39;m using Windows 7. I found that agent is running. But `ssh-add` is useless as it gives an error above.


ssh-agent error &quot;Could not open a connection to your authentication agent.&quot;

I need to add a public key to <code>ssh-agent</code> but I'm getting the following error
> Could not open a connection to your authentication agent.
I'm using Windows 7. I found that agent is running. But <code>ssh-add</code> is useless as it gives an error above.

I have set up ssh key pairs between my desktop and two servers, and from the servers to my desktop, but after reinstalling the OS on my desktop, I can&#39;t re-establish the key-pair going into my desktop by this: 

```shell
mkdir ~/.ssh
chmod 700 ~/.ssh
ssh-keygen -t 
ssh-copy-id username@server
```

I get the following error:

(names in *italics* changed to protect the innocent My desktop is Ubuntu, and I can&#39;t find the answer [ here][1])

   

&gt;  @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
&gt;     @    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
&gt;     @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
&gt;     IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
&gt;     Someone could be eavesdropping on you right now (man-in-the-middle
&gt; attack)!
&gt;     It is also possible that the RSA host key has just been changed.
&gt;     The fingerprint for the RSA key sent by the remote host is
&gt;     *ab:cd:ef:gh*
&gt;     Please contact your system administrator.
&gt;     Add correct host key in /home/*user*/.ssh/known_hosts to get
&gt; rid of this message.
&gt;     Offending key in /home/*user*/.ssh/known_hosts:1
&gt;     RSA host key for *user.server* has changed and you have requested strict
&gt; checking.
&gt;     Host key verification failed.

  [1]: https://help.ubuntu.com/community/SSH/OpenSSH/Keys


How to establish ssh key pair when &quot;Host key verification failed&quot;

I have the following boxes:

a) A Windows box with Eclipse CDT,  
b) A Linux box, accessible for me only via SSH.

Both the compiler and the hardware required to build and run my project is only on machine B.

I&#39;d like to work &quot;transparently&quot; from a Windows box on that project using Eclipse CDT and be able to build, run and debug the project remotely from within the IDE.

How do I set up that:

- The building will work? Any simpler solutions than writing a local makefile which would `rsync` the project and then call a remote makefile to initiate the actual build? Does Eclipse managed build have a feature for that?
- The debugging will work?
- Preferably - the Eclipse CDT code indexing will work? Do I have to copy all required header files from machine B to machine A and add them to include path manually?



Work on a remote project with Eclipse via SSH

Question as title.
Why is this, I have used the ssh command:
ssh -i mykey.pem root@xxx-xxx-xx-xx-xxx.compute-1.amazonaws.com
But i get that error, find nothing on google. What am I doing wrong?


SSHing into EC2 server via gives error Please login as the ec2-user user rather than root user

I think I forgot the passphrase for my SSH key, but I have a hunch what it might be.  How do I check if I&#39;m right?

How do I verify/check/test/validate my SSH passphrase?

I already have an ssh agent set up, and I can run commands on an external server in Bash script doing stuff like:

    ssh blah_server &quot;ls; pwd;&quot;

Now, what I&#39;d really like to do is run a lot of long commands on an external server. Enclosing all of these in between quotation marks would be quite ugly, and I&#39;d really rather avoid ssh&#39;ing multiple times just to avoid this. 

So, is there a way I can do this in one go enclosed in parentheses or something? I&#39;m looking for something along the lines of:

    ssh blah_server (
       ls some_folder;
       ./someaction.sh;
       pwd;
    )

Basically, I&#39;ll be happy with any solution as long as it&#39;s clean.

### Edit ###

To clarify, I&#39;m talking about this being part of a larger bash script. Other people might need to deal with the script down the line, so I&#39;d like to keep it clean. I don&#39;t want to have a bash script with one line that looks like:

    ssh blah_server &quot;ls some_folder; ./someaction.sh &#39;some params&#39;; pwd; ./some_other_action &#39;other params&#39;;&quot;

because it is extremely ugly and difficult to read.

What is the cleanest way to ssh and run multiple commands in Bash?

I created keys as instructed in the github tutorial, registered them with github, and tried using ssh-agent explicitly — yet git continues to ask me for my passphrase every time I try to do a pull or a push.

What could be the cause?

Git keeps asking me for my ssh key passphrase

I have a following problem:

    $ git push -u origin master
    Permission denied (publickey).
    fatal: Could not read from remote repository.

    Please make sure you have the correct access rights
    and the repository exists.

I have already checked the connection doing this:

    $ ssh -vT git@github.com

and output looks good, I was correctly authenticated.

While checking further, I noticed that:

    $ ssh-add -l
    The agent has no identities.
 
I have tried to run ssh-agent, but nothing changed:

    $ ssh-agent
    SSH_AUTH_SOCK=/tmp/ssh-A1mhFqvqncuO/agent.766; export SSH_AUTH_SOCK;
    SSH_AGENT_PID=767; export SSH_AGENT_PID;
    echo Agent pid 767;
    $ ssh-add -l
    Could not open a connection to your authentication agent.

I am using Arch Linux. Any help would be strong appreciated! Thanks in advance!

[Github diagnostic help here.][1]


  [1]: https://help.github.com/articles/error-permission-denied-publickey/

Cannot push to git repository - permission denied

I am running into this error of: 

&lt;!-- language: lang-none --&gt;

    $ git push heroku master
    Warning: Permanently added the RSA host key for IP address &#39;50.19.85.132&#39; to the list of known hosts.
    !  Your key with fingerprint b7:fd:15:25:02:8e:5f:06:4f:1c:af:f3:f0:c3:c2:65 is not authorized to access bitstarter.

I tried to add the keys and I get this error below:

&lt;!-- language: lang-none --&gt;

    $ ssh-add ~/.ssh/id_rsa.pub
    Could not open a connection to your authentication agent.

Could not open a connection to your authentication agent

I have a site as a remote Git repo pulling from Bitbucket.com using an SSH alias. I can manually start the ssh-agent on my server but I have to do this every time I login via SSH.

I manually start the ssh-agent:

    eval ssh-agent $SHELL

Then I add the agent:

    ssh-add ~/.ssh/bitbucket_id

Then it shows up when I do:

    ssh-add -l

And I&#39;m good to go. Is there any way to automate this process so I don&#39;t have to do it every time I login? The server is running RedHat 6.2 (Santiago).

Start ssh-agent on login

I am trying to find a nice way to restore the SSH agent when I reconnect a disconnected tmux session.

The cause seems to be that the SSH agent session changes but the environment variable from the tmux session is not updated.

How can I automate this, before attaching the session itself? Because the session I am attaching to does not always have a bash prompt, so I cannot afford to type something inside it. It has to be something to run before creating or attaching the tmux session.

An example of the code I&#39;m running is at https://gist.github.com/ssbarnea/8646491 -- a small ssh wrapper that is using tmux to create persistem ssh connections. This works quite well, but sometimes the ssh agent stops working so I am no longer able to use it to connect to other hosts.

ssh-agent error "Could not open a connection to your authentication agent."

Ssh Problem Overview

Ssh Solutions

Mark unit test as an expected failure in JUnit

C complex number and printf

Attributions