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How do I display star(*) instead of plain text for password c++

How can I do so that I can display star(*) instead of plain text for password in C++.

I am asking for password and it is plain pass on the screen.

How can I convert them in to star(*) so that user can not see the password while entering.

This is what I have currently

        char pass[10]={"test"};
        char pass1[10];
        textmode(C40);
        label开发者_运维百科:
        gotoxy(10,10);
        textcolor(3);
        cprintf("Enter password :: ");
        textcolor(15);
        gets(pass1);
        gotoxy(10,11);
        delay(3000);
        if(!(strcmp(pass,pass1)==0))
        {
          gotoxy(20,19);
          textcolor(5);
          cprintf("Invalid password");
          getch();
          clrscr();
          goto label;
        }

Thanks


You need to use an unbuffered input function, like getch () provided by curses library, or a console library of your OS. Calling this function will return the pressed key character, but will not echo. You can manually print * after you read each character with getch (). Also you need to write code if backspace is pressed, and appropriately correct the inserted password.

Here is a code which once i wrote with the curses. Compile with gcc file.c -o pass_prog -lcurses

#include <stdio.h>
#include <stdlib.h>
#include <curses.h>

#define ENOUGH_SIZE 256

#define ECHO_ON 1
#define ECHO_OFF 0

#define BACK_SPACE 127

char *my_getpass (int echo_state);

int main (void)
{
  char *pass;

  initscr ();

  printw ("Enter Password: ");
  pass = my_getpass (ECHO_ON);

  printw ("\nEntered Password: %s", pass);
  refresh ();
  getch ();
  endwin ();
  return 0;
}


char *my_getpass (int echo_state)
{
  char *pass, c;
  int i=0;

  pass = malloc (sizeof (char) * ENOUGH_SIZE);
  if (pass == NULL)
  {
    perror ("Exit");
    exit (1);
  }

  cbreak ();
  noecho ();

  while ((c=getch()) != '\n')
  {
    if (c == BACK_SPACE)
    {
      /* Do not let the buffer underflow */
      if (i > 0)
      { 
        i--;
        if (echo_state == ECHO_ON)
               printw ("\b \b");
      }
    }
    else if (c == '\t')
      ; /* Ignore tabs */
    else
    {
      pass[i] = c;
      i = (i >= ENOUGH_SIZE) ? ENOUGH_SIZE - 1 : i+1;
      if (echo_state == ECHO_ON)
        printw ("*");
    }
  }
  echo ();
  nocbreak ();
  /* Terminate the password string with NUL */
  pass[i] = '\0';
  endwin ();
  return pass;
}


There's nothing in C++ per se to support this. The functions in your example code suggest that you are using curses, or something similar; if so, check the cbreak and nocbreak functions. Once you've called cbreak, it's up to you to echo the characters, and you can echo whatever you like (or nothing, if you prefer).


#include<iostream.h>
#include<conio.h>
#include<stdio.h>
void main()
{
 clrscr();
 char a[10];
 for(int i=0;i<10;i++)
 {
  a[i]=getch();     //for taking a char. in array-'a' at i'th place 
  if(a[i]==13)      //cheking if user press's enter 
  break;            //breaking the loop if enter is pressed  
  printf("*");      //as there is no char. on screen we print '*'
 }
 a[i]='\0';         //inserting null char. at the end
 cout<<endl;
 for(i=0;a[i]!='\0';i++)  //printing array on the screen
 cout<<a[i];
 sleep(3);                //paused program for 3 second
}
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