Daniel Briceño's questions

I have a button in the main window, and the question came to me: ¿Como hago para eliminar ese mismo boton en tiempo de ejecucción. I thought to call the function: SendDlgItemMessage:

#include <windows.h>
#define ID_BUTTON 119
...
LRESULT CALLBACK WindowProcedure( HWND hwnd,UINT msg,WPARA wParam,LPARAM lParam ){
    switch(msg){
        case WM_CREATE:
            CreateWindow("button","Click Me for deleted mi.",WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON | WS_TABSTOP,200,200,40,20,hwnd,(HMENU)ID_BUTTON,NULL,0 );
            break;
        case WM_COMMAND:
            switch( wParam ){
                case ID_BUTTON:
                    SendDlgItemMessage( hwnd,ID_BUTTON,WM_DESTROY,0,0);
                break;
            }
            break;
...
    }
    return 0;
}

Since the button is really a window, I decided to send it the message WM_DESTROYso that it will close, but when I click it it doesn't close it and it doesn't disappear either. I have verified that if you call the function SendDlgItemMessagewith a simple MessageBox.
I haven't been able to do it on the internet, I only get: ¿Como crear un boton con win32Apis?, but what I want is to close it, not create it.

How do I close the button? or how did you remove it?

I have this C code:

#include <curses.h>
int main(){
    initscr();
    move(10,30);
    printf("Hola");
    return 0;
}

I get this error:

main.C:(.text+0xf): undefined refernce to 'initfscr'
main.C:(.text+0x23): undefined refernce to 'move'

The command gccis:

gcc main.c -o main.exe

I have installed it using the MinGW installer. How can I solve this problem?.
I've tried uninstalling and reinstalling it but it doesn't work.

Update:

I have also linked my project with the frag of -lncursesand I get the same problems:

gcc -lncurses main.c -o main.exe

My idea is simple: Identify the state of one element and change the style of another element accordingly:

I try this and the div element inside the threedot div doesn't change and stays invisible. How do I make this work?

/* El css: */
#trespuntos b:hover {
  display: none;
  #trespuntos div {
    display: block;
  }
}

#trespuntos b {
  font-size: 3em;
}

#trespuntos div {
  display: none;
}

<!-- El HTML: -->
<div id="trespuntos">Descripción:<b>...</b>
  <div>
    <h3>Beneficios:</h3>
    <ul>......</ul>
    <h3>Ploblemas:</h3>
    <ul>.......</ul>
  </div>
</div>

I want to make a game in MS-DOS and I'm stuck with a problem:

How to ask the user for input without stopping the console?

I've considered stopping it for a few milliseconds and giving the illusion that the console didn't stop:

@echo off
:inicio
choice /c awds0 /t 0.30 /d 0
if %errorlevel%==1 echo izquierda.
goto inicio
pause
exit

But it gives me an error:

Only a number from -1 to 999 is allowed

I have also tried to place:
choice /c awds0 /t 0 /d 0
But the key is not detected even if I put it in a buclegoto:

@echo off
:inicio
choice /c awds0 /t 0 /d 0
if not %errorlevel%==5 goto end
goto inicio
:end
echo se terminó el programa
pause
exit

input: a....

output: Infinity loop

External links:

• Answer from: Read key in batch? : This answer is pretty close to what I'm looking for, but running it freezes the console until I type the key.

I have this code:

char* texto=(char*)malloc(11);//Retorno un arrays de 10 char
strcpy(texto,"Hello World");
texto[4]='\0';//Recortamos la cadena.
for (int i=5;i<11;i++)
 free(&texto[i]);//Liberamos el espacio que no nesecitamos.

This stops the executable for me. But if I did this:

texto[7]='\0';
for (int i=8;i<11;i++)
 free(&texto[i]);

The executable ends perfectly. Because? And how do I solve it?
I got this page: Uncle C(GCC) There I could see this error:

double free or corruption (top)
/srv/wrappers/c-gcc: line 5:  3868 Aborted                 (core dumped) ./.bin.tio "$@" < .input.tio

But why if I am freeing memory that I reserve to trim the string?
Any help or advice. The idea is just to trim the string and free up the space I don't need.

As the title says:

How to identify the language type: C or C++ using a preprocessor?

I am making a resource file. Call ids.hthat I plan to use in programs for both C and C++. The idea is that if it's C a structure is compiled, but if it's C++ a class is compiled:

#ifdef _C_
typedef struct{/***@param Code*/}Cadena;
#elif _CPP_
class Cadena{
/**@param Code*/
};

#endif

The objective is to identify the language so that errors do not occur when executing it.

I am trying to make a function sqrt(); the function I got is very slow. How can I make it faster?

#include <stdio.h>
#include <math.h>
double root(double x);

int main(){
    printf("%f",root(3));
    printf("\n%f",sqrt(3));
    return 0;
}

double root(double x){
    long double a[9];
    long double b[9]={1.0,0.1,0.01,0.001,0.0001,0.00001,0.000001};
    
    int i=0;
    for(i=0;i<9;i++){
       a[i]=0.0;
    }

    i=-1;
    while(a[i]*a[i]!=x){
        if(i==8)
            i=-1;
        i++;
        a[i]+=b[i];
        if(a[6]*a[6]>x)
            return a[6];
        else if(a[5]*a[5]==x)
            return a[5];
        else if(a[4]*a[4]==x)
            return a[4];
    }
    return a[i];
}

I made this function on the basis that if you multiply all the numbers, you will be able to find the square root.