eval_server.js

var syscalls = require('syscalls')
var loop = require('./loop')

var fd = syscalls.socket(syscalls.AF_INET, syscalls.SOCK_STREAM, 0)
syscalls.fcntl(fd, syscalls.F_SETFL, syscalls.O_NONBLOCK)
syscalls.bind(fd, 3000, "0.0.0.0")
syscalls.listen(fd, 100)

loop.on(fd, 'read', function() {
  console.log("New connection")
  var connFd = syscalls.accept(fd)

  loop.on(connFd, 'read', function() {
    var code = syscalls.read(connFd, 10240)
    loop.remove(connFd, 'read')

    if (code.length == 0) {
      syscalls.close(connFd)
      return
    }

    if (syscalls.fork() == 0) {
      // In the child process
      console.log("Running in PID: " + syscalls.getpid())
      var result = eval(code)
      syscalls.write(connFd, JSON.stringify(result) + "\n")
      console.log("Done PID: " + syscalls.getpid())
      process.exit()

    } else {
      // In the master process
      syscalls.close(connFd)
    }
  })
})

loop.run()