joystick control program in c++

[bha123]

Hai friends

i am recently to use joystick inputs for my robotic project. for that i am actually trying to run the individual testing of sub classes . when i run the code i am getting the following error

In function int main()

error : " calloc was declared out of scope

The following is the code of program

The project was compiled in ubuntu 10.10

#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <linux/joystick.h>

#define JOY_DEV "/dev/js0"

int main()
{
    int joy_fd, *axis= NULL, num_of_axis = 0, num_of_buttons=0,x;
    
    char *button = NULL , name_of_joystick[80];
    
    struct js_event js;
    // input of joystick values to variable joy_fd
        
    if((joy_fd = open(JOY_DEV,O_RDONLY))== -1 )
    {
        printf(" couldn't open the joystick \n " );
        
        return -1;
    }

    ioctl(joy_fd, JSIOCGAXES , &num_of_axis);
    ioctl(joy_fd, JSIOCGBUTTONS , &num_of_buttons);
    ioctl(joy_fd, JSIOCGNAME(80), &name_of_joystick);
    
        axis = (int *) calloc(num_of_axis , sizeof(int));
        button = (char *) calloc( num_of_buttons , sizeof (char));
    
    printf( " Joy stick detected : %s \n \t %d axis \n\t %d buttons \n\n" ,name_of_joystick , num_of_axis , num_of_buttons);

    fcntl( joy_fd, F_SETFL , O_NONBLOCK ); // use non - blocking methods

    while(1) // infinite loop

    {
        // read the joystick 
        
        read (joy_fd, &js , sizeof(struct js_event));

        // see what to do with the event

        switch(js.type & ~ JS_EVENT_INIT)
        {
            case JS_EVENT_AXIS :
            
                axis [ js.number ] = js.value;
            
            case JS_EVENT_BUTTON :
            
                button [js.number ] = js.value;
        }

        // print the results


        printf( " X: %6d y: %6d ", axis[0] , axis[1]);
        
        if( num_of_axis > 2)

            printf( " Z: %6d " , axis[2] );
        if( num_of_axis > 3)

            printf( " R : %6d " , axis [3]);
 
        for( x=0 ; x<num_of_buttons ; ++x)
        
            printf( "B %d : %d " , x, button [x]);
        fflush(stdout);

    }
    
    close(joy_fd);

return 0;
}

can some one help me in this regard

[quzah]

calloc is in stdlib.h.


Quzah.

[Salem]

Lets see, you write a topic title containing "c++", yet you post in the C section of the forum.

Things improve with your post of actual C code.

But then it all heads south again which the .cpp attachment.

Are you entirely clear on which language you're using, or are you in the mistaken belief that they are somehow fully interchangeable?

Oh, and your switch/cases need break statements as well.