Possible Duplicate:
Read a password from std::cin
I don't work normally with the console, so my question is maybe very easy to answer or impossible to do .
Is it possible to "decou开发者_运维技巧ple" cin
and cout
, so that what I type into the console doesn't appear directly in it again?
I need this for letting the user typing a password and neither me nor the user normally wants his password appearing in plaintext
on the screen.
I tried using std::cin.tie
on a stringstream
, but everything I type is still mirrored in the console.
From How to Hide Text:
Windows
#include <iostream>
#include <string>
#include <windows.h>
using namespace std;
int main()
{
HANDLE hStdin = GetStdHandle(STD_INPUT_HANDLE);
DWORD mode = 0;
GetConsoleMode(hStdin, &mode);
SetConsoleMode(hStdin, mode & (~ENABLE_ECHO_INPUT));
string s;
getline(cin, s);
cout << s << endl;
return 0;
}//main
cleanup:
SetConsoleMode(hStdin, mode);
tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
Linux
#include <iostream>
#include <string>
#include <termios.h>
#include <unistd.h>
using namespace std;
int main()
{
termios oldt;
tcgetattr(STDIN_FILENO, &oldt);
termios newt = oldt;
newt.c_lflag &= ~ECHO;
tcsetattr(STDIN_FILENO, TCSANOW, &newt);
string s;
getline(cin, s);
cout << s << endl;
return 0;
}//main
You're really asking about two unrelated issues.
Calling cin.tie( NULL )
decouples std::cin
and std::cout
completely. But it doesn't affect anything at a lower level. And at the lowest level, at least under Windows and Unix, std::cin
and std::cout
are both connected to the same device at the system level, and it is that device (/dev/tty
under Unix) which does the echoing; you can even redirect standard out to a file, and the console will still echo input.
How you turn off this echoing depends on the system; the easiest solution is probably to use some sort of third party library, like curses or ncurses, which provides a higher level interface, and hides all the system dependencies.
Use getch()
to get the input instead of using cin
, so the input will not be shown (quoting wiki):
int getch(void) Reads a character directly from the console without buffer, and without echo.
This is really C, not C++, but it might suit you.
Also, there's another link here.
精彩评论