Password Timeframe

**Junior89** · 01-12-2005

Hi guys, just wondering how you would set a window for how long you have to enter a password, thanks!

**Zach L.** · 01-12-2005

Your gonna have to be more specific than that. It is a bit difficult to tell exactly what you are trying to do or what in particular you are having problems with.

Cheers

**jverkoey** · 01-12-2005

If you mean to only allow the user to type in their password for a certain amount of time, look in to the SetTimer win32 function.

http://msdn.microsoft.com/library/de...s/settimer.asp

**Kybo_Ren** · 01-12-2005

Use the functions in <ctime>

**Junior89** · 01-12-2005

yes i want to let the user only have a certain amount of time to enter the password, i think ive seen a way to do it with Sleep(). Any ideas?

**Hunter2** · 01-12-2005

Assuming you're doing a windows GUI application, read jverkoey's link.

If you're doing a console application, you can use the nonstandard kbhit() which is defined in conio.h to check if a key has been pressed already, inputting the next character of the password if a key has been pressed and then check if it's correct.. etc. Put it in a loop, and on each iteration of the loop check if the time has elapsed. You can use GetTickCount() if you have <windows.h> included to find how long the system has been running in milliseconds, otherwise use the functions in <ctime>. An alternative to kbhit() that has been suggested by Anonytmouse in the past is to get a handle to the console input using GetStdHandle() and checking if input is waiting using WaitForSingleObject().

**Junior89** · 01-12-2005

Hi Guys, I went with the GetTickCount() approach. I need one minor bit of help though. It lets you enter the password for as long as you want. I know the problem and that is that the cin.getline() command has a cin.ignore() function built in anyone know how to get it out?

Code:

#include <iostream>
#include <windows.h>

using namespace std;

int main()
{
    char password[25];
    int x=(GetTickCount()+3000);
    while(GetTickCount()<x)
    {
        cout<<"Password: ";
        cin.getline(password, 25);
    }       
    if(GetTickCount() >= x)
    {
        cout<<"DONE!";
    }
    if(strcmp(password,"password")==0)
    {
        cout<<"\nCorrect!";
    }
    else{
        cout<<"\nWrong!";
    }                
    cin.get();
    return 0;
}

**This is just a prototype program dont worry about how the password is hardcoded into the program

**Hunter2** · 01-12-2005

Code:

 DWORD start = GetTickCount();
     std::string pwd;
     cout << "Password: ";
     while(GetTickCount() - start < 10000) //10 seconds
     {
   if(kbhit())
	  pwd += (char)getch();
     }

Something like that should work.

**Junior89** · 01-12-2005

It wont compile, it says that kbhit() and getch() are undefined, that means the Header file is missing right? What header file is it under?

PS- What is a DWORD?

PSS- Any other ways?

**Hunter2** · 01-12-2005

kbhit() and getch() are in <conio.h>. You might not have it, since it isn't standard. Alternatively, you could write your own kbhit() function:

Code:

 bool kbhit()
 {
   HANDLE h = GetStdHandle(STD_INPUT_HANDLE);
   return (WaitForSingleObject(h, 0) == WAIT_OBJECT_0);
 }

The functions I used in that come from <windows.h>, which it seems you do have.

**EDIT**
DWORD stands for 'double word', and is just a microsoft typedef for unsigned long. The function GetTickCount() returns a value of type DWORD, so for the sake of being absolutely sure that everything will be compatible (on the offchance that MS decides to make DWORD something else in the future), we store the result in a DWORD instead of unsigned long.

Thread: Password Timeframe

Thread Tools

Search Thread

Display

Password Timeframe

Similar Threads

A tenet connection from a C program..

Problem reading a password from a file.

[Q]Hide Password

written command line password generator

password