我一直以为这两种是一样的，直到发现
cecil[@cecil-Aspire-4750](/user/cecil-Aspire-4750) ~/Dropbox/node node
> console.log(__dirname)
ReferenceError: __dirname is not defined
at repl:1:14
at REPLServer.self.eval (repl.js:110:21)
at Interface.<anonymous> (repl.js:239:12)
at Interface.EventEmitter.emit (events.js:95:17)
at Interface._onLine (readline.js:202:10)
at Interface._line (readline.js:531:8)
at Interface._ttyWrite (readline.js:760:14)
at ReadStream.onkeypress (readline.js:99:10)
at ReadStream.EventEmitter.emit (events.js:98:17)
at emitKey (readline.js:1095:12)
而这样却可以
✘ cecil[@cecil-Aspire-4750](/user/cecil-Aspire-4750) ~/Dropbox/node echo "console.log(__dirname)" > test.js
cecil[@cecil-Aspire-4750](/user/cecil-Aspire-4750) ~/Dropbox/node node test.js
/home/cecil/Dropbox/node
我想知道为什么会这样，这两种模式有什么本质上的不同吗？ 可能有点钻牛角尖了
2 回复
The name of the directory that the currently executing script resides in.
from http://nodejs.org/api/globals.html#globals_dirname
首先你得是个 script
REPL其实也可以得到：
PS C:\mongodb\bin> node
> process.cwd()
'C:\\mongodb\\bin'
这个并没有如此简单吧，我在学习这篇的时候 mongoose教程 在REPL下会抛出
> personEntity.speak();
TypeError: Object { name: 'Krouky', _id: 52f48d9dba3964b539a9acff } has no method 'speak'
at repl:1:14
at REPLServer.self.eval (repl.js:110:21)
at repl.js:249:20
at REPLServer.self.eval (repl.js:122:7)
at Interface.<anonymous> (repl.js:239:12)
at Interface.EventEmitter.emit (events.js:95:17)
at Interface._onLine (readline.js:202:10)
at Interface._line (readline.js:531:8)
at Interface._ttyWrite (readline.js:760:14)
at ReadStream.onkeypress (readline.js:99:10)
