Add options.noEchoBack.

README.md

@@ -30,18 +30,20 @@ Sets the prompt, for example when you run `node` on the command line, you see `>
 ### prompt
 
 ```js
-line = readlineSync.prompt()
+line = readlineSync.prompt([options])
 ```
 
 Readies readline for input from the user, putting the current `setPrompt` options on a new line, giving the user a new spot to write.  
+If `{noEchoBack: true}` is specified to `options`, echo back is avoided. It is used to hide the password which is typed by user on screen. *See [Note](#note) for security.*
 
 ### question
 
 ```js
-line = readlineSync.question(query)
+line = readlineSync.question(query[, options])
 ```
 
 Displays the `query` to the user, and then returns the user's response after it has been typed.  
+If `{noEchoBack: true}` is specified to `options`, echo back is avoided. It is used to hide the password which is typed by user on screen. *See [Note](#note) for security.*
 
 ### setEncoding
 
@@ -74,7 +76,7 @@ readlineSync.setPrint(function(display, encoding) {
 
 console.log('Your account required.'.grey);
 user = readlineSync.question('USER NAME'.white.inverse + ': ');
-pw = readlineSync.question('PASSWORD'.white.inverse + ': ', true);
+pw = readlineSync.question('PASSWORD'.white.inverse + ': ', {noEchoBack: true});
 // Authorization ...
 console.log(('Welcome, ' + user + '!').green.bold);
 
@@ -82,8 +84,8 @@ readlineSync.setPrompt('> '.bold.red);
 cmd = readlineSync.prompt();
 ```
 
-## Note
-The your Node and OS may not support interactively reading from stdin. The stdin interfaces are different by platforms.  
+## <a name ="note">Note</a>
++ The your Node and OS may not support interactively reading from stdin. The stdin interfaces are different by platforms.  
 If in those platforms, an error is thrown.
 
 ```js
@@ -95,8 +97,11 @@ try {
 }
 ```
 
++ If `options.noEchoBack` is used, the text that input by user is saved to temporary file (e.g. `/tmp/readline-sync.stdout`). This file is removed immediately after reading is done, but you have to be careful about it because this text is *plain*. Removing the file might fail, or the file might be peeped before it is removed.
+
 ## Release History
- * 2014-07-12			v0.3.0			Add setPrint().
+ * 2014-07-12			v0.4.0			Add `options.noEchoBack`.
+ * 2014-07-12			v0.3.0			Add `setPrint()`.
  * 2014-06-27			v0.2.3			Add alternative reading via shell on the environment which don't support interactively reading.
  * 2013-12-18			v0.2.2			Error handle for the environment which don't support interactively reading from stdin.
  * 2013-08-30			v0.2.0			Rewrite exporting methods.

lib/read.bat

@@ -1,6 +1,11 @@
 @echo off
 setlocal
-set /p LINE=<CON >CON
+if "%1"=="noechoback" (
+  set /p LINE=<CON >NUL
+  echo; >CON
+) else (
+  set /p LINE=<CON >CON
+)
 set /p DUM="%LINE%"<NUL
 endlocal
 exit /b 0

lib/read.sh

@@ -1,3 +1,10 @@
-read LINE </dev/tty
+if [ "$1" = "noechoback" ]; then
+  stty -F /dev/tty -echo echonl
+  read LINE </dev/tty
+  stty -F /dev/tty echo -echonl
+  # printf '\n' >/dev/tty
+else
+  read LINE </dev/tty
+fi
 printf '%s' "$LINE"
 exit 0

lib/readline-sync.js

@@ -17,7 +17,7 @@ var promptText = '> ',
   buffer = new Buffer(BUF_SIZE),
   useShell = true, print, tempdir;
 
-function _readlineSync(display) {
+function _readlineSync(display, options) {
   var input = '', rsize, err;
 
   if (display) {
@@ -25,6 +25,16 @@ function _readlineSync(display) {
     stdout.write(display, encoding);
   }
 
+  if (options && options.noEchoBack) { // Try reading via shell
+
+    input = _readlineShell(true);
+    if (typeof input !== 'string') {
+      if (display) { stdout.write('\n', encoding); } // Return from prompt line.
+      throw new Error('Can\'t read via shell');
+    }
+
+  } else {
+
     stdin.resume();
     while (true) {
       rsize = 0;
@@ -57,24 +67,28 @@ function _readlineSync(display) {
     }
     stdin.pause();
 
+  }
+
   return input.trim();
 }
 
-function _readlineShell() {
+function _readlineShell(noEchoBack) {
   // piping via files instead of execSync (node v0.12+)
   var shellPath, args, shellStdout,
     pathStdout = getTempfile('readline-sync.stdout'),
     pathStatus = getTempfile('readline-sync.status'),
-    pathDone   = getTempfile('readline-sync.done');
+    pathDone   = getTempfile('readline-sync.done'),
+    optEchoBack = noEchoBack ? ' noechoback' : '';
 
   if (process.platform === 'win32') {
     // The quote (") is escaped by node before parsed by shell. Then use ENV{Q}.
     shellPath = 'cmd.exe';
-    args = ['/V:ON', '/S', '/C', '%Q%' + __dirname + '\\read.bat%Q% >%Q%' + pathStdout +
+    args = ['/V:ON', '/S', '/C',
+      '%Q%' + __dirname + '\\read.bat%Q%' + optEchoBack + ' >%Q%' + pathStdout +
       '%Q% & (echo !ERRORLEVEL!)>%Q%' + pathStatus + '%Q% & (echo 1)>%Q%' + pathDone + '%Q%'];
   } else {
     shellPath = '/bin/sh';
-    args = ['-c', '(' + shellPath + ' "' + __dirname + '/read.sh") >"' + pathStdout +
+    args = ['-c', '(' + shellPath + ' "' + __dirname + '/read.sh"' + optEchoBack + ') >"' + pathStdout +
       '"; echo $? >"' + pathStatus + '"; echo 1 >"' + pathDone + '"'];
   }
 
@@ -133,10 +147,10 @@ exports.setEncoding = function(newEncoding) {
   }
 };
 
-exports.prompt = function() {
-  return _readlineSync(promptText);
+exports.prompt = function(options) {
+  return _readlineSync(promptText, options);
 };
 
-exports.question = function(query) {
-  return _readlineSync(typeof query === 'string' ? query : '');
+exports.question = function(query, options) {
+  return _readlineSync(typeof query === 'string' ? query : '', options);
 };

package.json

@@ -1,7 +1,7 @@
 {
   "name": "readline-sync",
   "description": "Synchronous Readline",
-  "version": "0.3.0",
+  "version": "0.4.0",
   "homepage": "https://github.com/anseki/readline-sync",
   "author": {
     "name": "anseki"