def waitForContainerToLaunch(self, readyString, process, suppressOutput):
    while True:
      where = process.stderr_file.tell()
      line = process.stderr_file.readline()
      while (not line):# or (line[-1:] != '\n'):
        time.sleep(0.1)
        process.stderr_file.seek(where)
        line = process.stderr_file.readline()
      if not suppressOutput:
        subuserlib.print.printWithoutCrashing(line[:-1])
      if readyString in line:
        break
    process.stderr_file.close()