redirect char input console

amad1337 · #1 25-Jul-2005, 11:09

I'am working with project that will be a console app.
Idont want to get in detail about my console app but what iam trying to do is to get a password string from the user in the same time i want to put that input char in the password string and output star kind of char in the output.

like this...
password:*******

So guys is there a way to stop the output of char in same time access it from stdin file??

I hope someone understand my question

nkhambal · #2 25-Jul-2005, 13:11

check this tutorial.

How to hide characters from being displayed on screen as they are keyed in?

I used the linux_getch() function with little modification to print "*" when user is entering the password.

CPP / C++ / C Code:

int ci_getpass(void) 
{
  struct termios oldstuff;
  struct termios newstuff;
  int    inch;
  
  tcgetattr(STDIN_FILENO, &oldstuff);
  newstuff = oldstuff;                  /* save old attributes               */
  newstuff.c_lflag &= ~(ICANON | ECHO); /* reset "canonical" and "echo" flags*/
  tcsetattr(STDIN_FILENO, TCSANOW, &newstuff); /* set new attributes         */
  inch = getchar();
  if (inch=='\n')
  {
	  tcsetattr(STDIN_FILENO, TCSANOW, &oldstuff); /* restore old attributes     */
	  return inch;
  } else {
  printf("*");
  return inch;
  }
}

Also, check this other thread.

Thanks,

amad1337 · #3 25-Jul-2005, 13:55

thx for the replay....

I frogot to mention that iam on win(xp) os.
<termios.h> is on linux os...

so is't a way to make that hapen.

Iam using visual 6 c++ and my project is win32 console application (my source is only in c).

davekw7x · #4 25-Jul-2005, 14:02

Quote:

Originally Posted by amad1337

thx for the replay....

I frogot to mention that iam on win(xp) os.
<termios.h> is on linux os...

so is't a way to make that hapen.

Iam using visual 6 c++ and my project is win32 console application (my source is only in c).

The thread in the link was a response to someone who had used getch() in Windows and wanted an equivalent for Linux.

If you #include <conio.h>, you may be able to use getch(). (It is system-dependent. Older Microsoft compilers, including VC++ 6, have it; newer ones may not.)

These are two system-dependent ways of using functions that are not part of the C standard, and, therefore, are not portable, but one or the other may be suitable for your purposes

Regards,

Dave

amad1337 · #5 25-Jul-2005, 15:04

davekw7x thx very much m8 you saved me from killing my self

I got it fanily

CPP / C++ / C Code:

#include <stdio.h>
#include <conio.h>
main()
{
    char c;
    
    c = getch();
   
   while(c != '\r')
   {
      if(isalnum(c))
      {
         printf("%c", 42);
      }
      c = getch();
   } 
}

damn i love this forum

WaltP · #6 25-Jul-2005, 17:52

What if the user doesn't enter an alphanumeric? You should warn them:

CPP / C++ / C Code:

#include <stdio.h>
#include <conio.h>
int main()
{
    char c;
    
    c = getch();
   
   while(c != '\r')
   {
      if(isalnum(c))
      {
         putch('*');
      }
      else
      if (c != '\r')
      {
         putch(0x07);
      }
      c = getch();
   } 
   return 0;
}

I also changed your printf()s to remove the huge overhead that printf() demands. putch() is much better for outputting a single character. Output a bell (ctrl-G). There's also \ version which would be more standard. Is it \b? Can't remember.

Also you need int main() and a return in your code.

davekw7x · #7 25-Jul-2005, 18:11

Quote:

Originally Posted by WaltP

Output a bell (ctrl-G). There's also \ version which would be more standard. Is it \b? Can't remember.
.

The Standard escape is '\a' (alarm). The effect of putchar('\a') is system-dependent, and may or may not cause a "beep".

Regards,

Dave

amad1337 · #8 25-Jul-2005, 22:00

thx davekw7x...

the code i wrote was just ex so it wasn't the greates.. The code i will use in my project will handle if the user uses isspace(c).

thx for help

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