Nodejs Child Process:从已经初始化的进程写入stdin

Question

我正在尝试phantomjs使用节点生成外部进程child_process,然后在初始化后将信息发送到该进程,这可能吗？

我有以下代码:

var spawn = require('child_process').spawn,
    child = spawn('phantomjs');

child.stdin.setEncoding = 'utf-8';
child.stdout.pipe(process.stdout);

child.stdin.write("console.log('Hello from PhantomJS')");

但我在stdout上唯一得到的是phantomjs控制台的初始提示.

phantomjs> 

所以似乎child.stdin.write没有产生任何影响.

我不确定我是否可以在初始产卵时向phantomjs发送更多信息.

提前致谢.

Answer 1

您还需要传递\n符号才能使命令工作:

var spawn = require('child_process').spawn,
    child = spawn('phantomjs');

child.stdin.setEncoding('utf-8');
child.stdout.pipe(process.stdout);

child.stdin.write("console.log('Hello from PhantomJS')\n");

child.stdin.end(); /// this call seems necessary, at least with plain node.js executable

Answer 2

您需要用and包围您的write方法，该方法会刷新自调用以来缓冲的所有数据。也会刷新数据，但不再接受数据。corkuncorkuncorkcorkchild.stdin.end()

var spawn = require('child_process').spawn,
    child = spawn('phantomjs');

child.stdin.setEncoding('utf-8');
child.stdout.pipe(process.stdout);

child.stdin.cork();
child.stdin.write("console.log('Hello from PhantomJS')\n");
child.stdin.uncork();