linux – clamav-daemon start condition failed, /var/lib/clamav/daily.{c[vl]d,inc} was not met

After installing Modoboa(Open Source Mail Hosting), I Tried to start clamav-daemon, but i faced start condition failed.

    systemctl status clamav-daemon.service
    clamav-daemon.service - Clam AntiVirus userspace daemon
   Loaded: loaded (/lib/systemd/system/clamav-daemon.service; enabled; vendor preset: enabled)
  Drop-In: /etc/systemd/system/clamav-daemon.service.d
           └─extend.conf
   Active: inactive (dead)
Condition: start condition failed at Fri 2021-01-15 04:19:06 EST; 33min ago
           └─ ConditionPathExistsGlob=/var/lib/clamav/daily.{c(vl)d,inc} was not met

Below it showed the problem, conditionPathExistsGlob=/var/lib/clamav/daily.{c(vl)d,inc} was not met.
I couldn’t start the service with systemctl or other commands.
After some troubleshoots, I found out that /var/lib/clamav is empty and there should be some .cvd update file.
Also I couldn’t update the clamav with this command (show me 403 error):

sudo clamav-freshclam

what can I do now?

set theory – Condition for a point to be a limit point of some set in general topology

I generated many topological spaces for certain finite sets.
{{}, {1}, {2}, {4}, {1, 2}, {1, 3}, {1, 4}, {2, 4}, {1, 2, 3}, {1, 2,
4}, {1, 3, 4}, {1, 2, 3, 4}};
{{}, {1}, {4}, {1, 2}, {1, 3}, {1, 4}, {1, 2, 3}, {1, 2, 4}, {1, 3,
4}, {1, 2, 3, 4}};
{{}, {1}, {2}, {1, 2}, {2, 3}, {2, 4}, {1, 2, 3}, {1, 2, 4}, {2, 3,
4}, {1, 2, 3, 4}}.

I noticed a pattern that when {a} isn’t an open set, ‘a’ is a limit point of some subset of X.
I tried to prove it the following way using an example.
{{}, {1}, {2}, {4}, {1, 2}, {1, 3}, {1, 4}, {2, 4}, {1, 2, 3}, {1, 2,
4}, {1, 3, 4}, {1, 2, 3, 4}}
1,2,4 etc can’t be limit points because {1}, {2}, {4} are open sets.

If {1,3} is open, {2,3} can’t be open because their intersection is {3}(which isn’t open).
Any higher set will have to contain {1,3} in it, thus making 3 the limit point of any set containing 1.
This condition seems quite strong. I haven’t seen it being mentioned anywhere.
So i want to be sure if my argument is correct.

google sheets – Count number of rows with a specific MONTH in the date of a specific cell and a boolean condition in another cell

Let’s say I have a number of dates and whether they occupy full or half a day…

   DATE  |         WHAT        | HALF?
...
2021-4-1 | Something Something | false
2021-4-2 | Something Something | false
2021-4-5 | Something Something | false
2021-4-19| Something Something | true
2021-5-13| Something Something | false
2021-5-24| Something Something | false
2021-9-13| Something Something | true
...

I now want for each month the amount of half-days occupied in that list.
(e.g. for April that should be 1 in the examples above, for May that should be 0)

I.e. in pseudocode, I’m looking for something like

=COUNTIF(A8:A, `MOTH of row = MONTH(E2)` AND `half of row = true`)

where E2, in this case, is e.g. January stored as a date

and A8:A contains the dates of the above table (i.e. B8:B contains the WHAT and C8:C contains the HALF?)

plugins – Remove a div class with condition

Hi all I am newbie in wordpress

I have a problem in remove or override an action/function in my parent theme
my goal is show a display-job-card simply just a currency symbol with condition
in my child theme.

below are code in my parent theme:

<div class="flex-master card-job-price text-right text-vertical-center">

                <?php if ( get_option( 'wpjobster_packages_enabled' ) == 'yes' && get_post_meta( $pid, 'job_packages', true ) == 'yes' && $package_price_vals ) { ?>

                    <span class="small-job"><?php _e( 'Starting at', 'wpjobster' ); ?></span>
                    <span class="display-price-card"><?php echo wpjobster_get_show_price( min( $package_price_vals ) ); ?></span>

                <?php } elseif ( get_post_meta( $pid, 'price_type', true ) ) { ?>

                    <span class="small-job"><?php echo sprintf( __( '%s Rate', 'wpjobster' ), wpjobster_translate_string( get_post_meta( $pid, 'price_type', true ) ) ); ?></span>
                    <span class="display-price-card"><?php echo wpjobster_get_show_price( get_post_meta( $pid, 'price', true ), 2, true ); ?></span>

                <?php } else { echo wpjobster_get_show_price( get_post_meta( $pid, 'price', true ), 2, true ); } ?>

            </div>

I have three types of ‘price_type’ custom/package and fixed.
I would like to show “display-price-card” under price_type (package and fixed) only.
I am not asking for the exact code. I am hoping someone who could give me some guidelines,
logic.

I’ve done a lot of research however, i can’t find any apply_filter nor do_action in here.
I am not sure how i can get into this class and how to o it right…

Please help and thanks all of you!

How to check the stability condition for matrix?

I have a code that in it I need to check the stability condition. These condition induces that my 6*6 matrix have real negative eigenvalues. I want to check that if all of the real eigenvalues for each j are negative, keep these answer as stable if not kept as not stable. how can I do that?

A = ( {
    {-(Kappa)/2, (CapitalDelta)c(j), -G(j)*Po(j), 0, 0, 0},
    {-(CapitalDelta)c(j), -(Kappa)/2, G(j)*Qo(j), 0, 0, 0},
    {0, 0, 0, (CapitalOmega)m, 0, 0},
    {G(j)*Qo(j), G(j)*Po(j), -(CapitalOmega)mm(j), -(Gamma)m, 
     Sqrt(2)*gw*Qw, Sqrt(2)*gw*Pw},
    {0, 0, -Sqrt(2)*gw*Pw, 0, -(Kappa)w/2, (CapitalDelta)w(j)},
    {0, 0, Sqrt(2)*gw*Qw, 0, -(CapitalDelta)w(j), -(Kappa)w/2}
   } );

I have these matrix that all parameters are fix and it is the answer of numerical solve for each j. I create eigenvalues by these

Re(Eigenvalues(A));
egn1 = Re(Eigenvalues(A)((1))) < 0;
egn2 = Re(Eigenvalues(A)((2))) < 0;
eng3 = Re(Eigenvalues(A)((3))) < 0;
eng4 = Re(Eigenvalues(A)((4))) < 0;
eng5 = Re(Eigenvalues(A)((5))) < 0;
eng6 = Re(Eigenvalues(A)((6))) < 0;

google sheets – Keep cell value same if condition is not met

Set-up

I have 2 Google sheets.

Sheet 1 imports a cell value from Sheet 2 using the IMPORTRANGE function.

The cell value in Sheet 2 is updated automatically each day, 365 days a year.

Sheet 1 contains data on 1 month only.


Issue

I need to create an IF formula using the IMPORTRANGE in Sheet 1 such that the cell value in Sheet 1 keeps the data from the last day of the month if the current date is a new month.

E.g. on February 1, the cell in Sheet 1 needs to display the data from January 31 and not from February 1, even though IMPORTRANGE imports the cell value from Sheet 2 which will contain data on February 1.


Pseudo formula

So, if Sheet 1 is about January, the formula in the cell in Sheet 1 should be something along the lines of,

IF(today(month())=1;IMPORTRANGE(Sheet2_url,cell_range);DONTCHANGEVALUE)

How do I go about?

execution condition for buffer overflow

You need to have root privileges to modify your password. This can be done by supplying the passwd utility with your user (non-root) password, since that utility is setuid and automatically runs itself as root no matter who executes it. If it verifies that the password you gave it matches the password on record for that user, it will allow you to change it by editing /etc/shadow for you.

There are many ways to get root on a system that you only have unprivileged local access to. This type of attack is termed local privilege escalation, or LPE. It usually relies on attacking a vulnerable setuid application, or attacking the kernel itself. Both of these require exploit development knowledge, which is not something someone can learn in one day, nor is it something that can be captured in a single answer here. If the system is running outdated software, you may be able to find a public vulnerability which you could use to elevate privileges. Otherwise, don’t count on it.

As for using a buffer overflow exclusively, that’s not going to work on any modern software. It might have worked in the 90s, but not today. There are numerous security techniques employed that make the naïve buffer overflow a thing of the past. Nowadays you need to bypass those techniques, which is not trivial. If you want to begin learning binary exploitation, start with a tutorial where you learn to exploit an intentionally insecure application with all the modern exploit mitigations manually disabled. Eventually you’ll start learning how to perform the exploit even with mitigations in place (e.g. learning how to execute code in non-executable memory by leveraging ROP). This is the kind of thing you’ll have to understand before exploiting a modern system with all the security in place.

c++ – Bidirectional thread communication with multiple condition_variable has rare hang / race condition

I have a rather strange example, and so I will just put the context out here briefly, and we can hopefully just pretend it’s a good idea.

I’m using a profiler that requires regular calls to its FRAME() macro so that it knows where CPU frames of a game start and end (the object the macro builds is RAII/scope based). I’m using fibers for my threading (main ‘thread’ is also a fiber worker), and this profiling macro only supports being called from a thread not registered with the profiler as a fiber worker thread. Ergo, I have this awful solution in the short-term, where I communicate to a separate thread just for this macro. The goal is to get the timing of construction/destruction of the RAII object as accurate as possible on this separate thread without disrupting the calling thread’s timing. But sometimes, the entire application hangs. I don’t understand how that’s possible here.

Main ‘thread’ (actually on a fiber but that doesn’t matter) / game loop:

FrameProfile frameProfile("Client Update");
while (!bShouldQuit)
{
    frameProfile.StartFrame();
    
    /* Do the game client's work for this frame */

    frameProfile.EndFrame();
}

And then this FrameProfile object is responsible for spinning up a separate thread, and will let that thread enter the FRAME macro scope when StartFrame is called from the above, and that thread will sleep in that scope until EndFrame is called, at which point it will wake up and exit the scope, destroying the profiler’s frame-measuring object, and giving us a hopefully-accurate frame time.

struct FrameProfile
{
    FrameProfile(const char* tag)
    {
        pthread_ = std::make_unique<std::thread>(
            (tag, this)(std::atomic_bool& killFlag) {
                while (!killFlag)
                {
                    assert(!endThreadFrame.WasSignalled());
                    startThreadFrame.WaitConsume();
                    {
                        assert(!startThreadFrame.WasSignalled());
                        assert(!endedThreadFrame.WasSignalled());

                        // Construct the frame-measuring object using this macro
                        OPTICK_FRAME(tag);

                        startedThreadFrame.Signal();

                        endThreadFrame.WaitConsume();
                        // endThreadFrame has been signalled - we need to exit scope
                        // to finish measuring ASAP
                    }
                    assert(!endThreadFrame.WasSignalled());
                    endedThreadFrame.Signal();
                }
            },
            std::ref(bKill_)
        );
    }

    ~FrameProfile()
    {
        bKill_ = true;
        if (pthread_)
        {
            if (pthread_->joinable())
            {
                pthread_->join();
            }
        }
    }

    void StartFrame()
    {
        assert(!startThreadFrame.WasSignalled());
        assert(!startedThreadFrame.WasSignalled());

        // Tell thread to start measuring the frame
        startThreadFrame.Signal();

        // Wait for thread to have started frame measurement
        startedThreadFrame.WaitConsume();
    }
    void EndFrame()
    {
        assert(!endThreadFrame.WasSignalled());
        assert(!endedThreadFrame.WasSignalled());

        // Tell thread to end frame measurement
        endThreadFrame.Signal();

        // Wait for thread to have ended frame measurement
        endedThreadFrame.WaitConsume();
    }


private:
    std::unique_ptr<std::thread> pthread_;
    std::atomic_bool bKill_ = false;

    struct ThreadSignal
    {
        std::atomic_bool bSignalled;
        std::mutex mutex;
        std::condition_variable cv;

        void Signal()
        {
            assert(!bSignalled);
            {
                std::unique_lock<std::mutex> _(mutex);
                bSignalled = true;
            }
            cv.notify_all();
        }

        bool WasSignalled()
        {
            return bSignalled;
        }

        void WaitConsume()
        {
            std::unique_lock unique(mutex);
            cv.wait(unique, (this)() { return bSignalled == true; });
            unique.unlock();
            bSignalled = false;
        }
    };

    ThreadSignal startThreadFrame;
    ThreadSignal endThreadFrame;

    ThreadSignal startedThreadFrame;
    ThreadSignal endedThreadFrame;
};

Can you spot what I’m doing wrong here? Or even a much better solution, I’d be open to it! It’s rare but it hangs sometimes – one of the ‘ThreadSignal’ objects will have its bool as ‘true’, but will still be stuck – I guess there’s a rare timing issue here.

Many thanks! Been tearing my hair out.

multivariable calculus – Prove that limit of a function exists if following condition is true.

The definition of limit my calculus textbook gives is:

We say that lim(x,y)→(a,b)f(x,y)=L, provided that:

1) Every neighbourhood of (a,b) contains points of the domain of f different from (a,b), and

2) For every positive number ϵ there exists a positive number δ=δ(ϵ) such that |f(x,y)−L|<ϵ holds 
whenever 
(x,y) is in the domain of f and satisfies 0< ((x−a)^2+(y−b)^2)^(1/2) < δ

How can we prove this definition??

python – Looking to take a list of strings as an output and turn it into a dictionary with the following condition

I was looking to turn this String List output into a python dictionary and associate each string or integer after the ‘:’ to the key value associated on the left. After creating a dictionary for this, I would also like to filter it to show only the key values that have an integer or float. I have posted the code below that currently gets me this output. All advice/help is appreciated. Thank you.

Python Input

result = c.get_quote(“TSLA”)

mymap = (json.dumps(result.json(), indent=4))

print(mymap)

Output

{
“TSLA”: {
“assetType”: “EQUITY”,
“assetMainType”: “EQUITY”,
“symbol”: “TSLA”,
“description”: “Tesla, Inc. – Common Stock”,
“bidPrice”: 676.7,
“bidSize”: 200,