text: // Copyright Joyent, Inc. and other Node contributors.
  //
  // Permission is hereby granted, free of charge, to any person obtaining a
  // copy of this software and associated documentation files (the
  // "Software"), to deal in the Software without restriction, including
  // without limitation the rights to use, copy, modify, merge, publish,
  // distribute, sublicense, and/or sell copies of the Software, and to permit
  // persons to whom the Software is furnished to do so, subject to the
  // following conditions:
  //
  // The above copyright notice and this permission notice shall be included
  // in all copies or substantial portions of the Software.
  //
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
  // NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
  // DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  // USE OR OTHER DEALINGS IN THE SOFTWARE.
  
  var common = require('../common');
  var assert = require('assert');
  
  console.log('process.pid: ' + process.pid);
  
  var first = 0,
      second = 0;
  
  var sighup = false;
  
  process.addListener('SIGUSR1', function() {
    console.log('Interrupted by SIGUSR1');
    first += 1;
  });
  
  process.addListener('SIGUSR1', function() {
    second += 1;
    setTimeout(function() {
      console.log('End.');
      process.exit(0);
    }, 5);
  });
  
  var i = 0;
  setInterval(function() {
    console.log('running process...' + ++i);
  
    if (i == 5) {
      process.kill(process.pid, 'SIGUSR1');
    }
  }, 1);
  
  // Test addListener condition where a watcher for SIGNAL
  // has been previously registered, and `process.listeners(SIGNAL).length === 1`
  process.addListener('SIGHUP', function () {});
  process.removeAllListeners('SIGHUP');
  process.addListener('SIGHUP', function () { sighup = true });
  process.kill(process.pid, 'SIGHUP');
  
  process.addListener('exit', function() {
    assert.equal(1, first);
    assert.equal(1, second);
    assert.equal(true, sighup);
  });
  