C program to design flying characters Screen Saver

Write a C program to design flying characters Screen Saver. This C program will display flying characters just like a Screen Saver.

Here is a set of characters that will access randomly and position on the screen will also random and on the random position program will display random character from assigned set of characters until user does not press any key.

Below is the source code of the C program to design flying characters Screen Saver which is successfully compiled and run on the windows system.The Output of the program is shown below.

SOURCE : :

#include <stdio.h>
#include <termios.h>
#include <unistd.h>
#include <fcntl.h>
 
/*will return character based on passed number*/
char getCHAR(int n)
{
    char ok[]="~!@#$%^&*:;'\",{}|<>=";
    return ok[n];
}
 
/*function to identify that any key hit by the keyboard*/
int kbhit(void)
{
  struct termios oldt, newt;
  int ch;
  int oldf;
  
  tcgetattr(STDIN_FILENO, &oldt);
  newt = oldt;
  newt.c_lflag &= ~(ICANON | ECHO);
  tcsetattr(STDIN_FILENO, TCSANOW, &newt);
  oldf = fcntl(STDIN_FILENO, F_GETFL, 0);
  fcntl(STDIN_FILENO, F_SETFL, oldf | O_NONBLOCK);
  
  ch = getchar();
  
  tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
  fcntl(STDIN_FILENO, F_SETFL, oldf);
  
  if(ch != EOF)
  {
    ungetc(ch, stdin);
    return 1;
  }
  
  return 0;
}
  
/*move cursor on specified position on screen*/
void gotoxy(int x,int y)
{
printf("%c[%d;%df",0x1B,y,x);
}
 
int main(void) {
    int x,y;
    long int i,j;
    i=j=0;
 
    x=1; y=20;
    system("clear");
 
    /*program will run until any key hit*/
    while(!kbhit())
    {
        x=rand()%((150-1+1)+1);
        y=rand()%((50-1+1)+1);
        gotoxy(x,y);
        printf("%c", getCHAR(rand()%((20-1+1)+1))); fflush(stdout);
        ++i;
        if(i==10000) {++j; i=0;}
        if(j==100000){ i=0;}
        if(j<=100)
            usleep(30000);
        if(j<=1000)
            usleep(3000);
        if(j<=10000)
            usleep(300);
    }
    return 0;
}

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