code: def start_ray_process(
      command: List[str],
      process_type: str,
      fate_share: bool,
      env_updates: Optional[dict] = None,
      cwd: Optional[str] = None,
      use_valgrind: bool = False,
      use_gdb: bool = False,
      use_valgrind_profiler: bool = False,
      use_perftools_profiler: bool = False,
      use_tmux: bool = False,
      stdout_file: Optional[str] = None,
      stderr_file: Optional[str] = None,
      pipe_stdin: bool = False,
  ):
      """Start one of the Ray processes.
  
      TODO(rkn): We need to figure out how these commands interact. For example,
      it may only make sense to start a process in gdb if we also start it in
      tmux. Similarly, certain combinations probably don't make sense, like
      simultaneously running the process in valgrind and the profiler.
  
      Args:
          command: The command to use to start the Ray process.
          process_type: The type of the process that is being started
              (e.g., "raylet").
          fate_share: If true, the child will be killed if its parent (us) dies.
              True must only be passed after detection of this functionality.
          env_updates: A dictionary of additional environment variables to
              run the command with (in addition to the caller's environment
              variables).
          cwd: The directory to run the process in.
          use_valgrind: True if we should start the process in valgrind.
          use_gdb: True if we should start the process in gdb.
          use_valgrind_profiler: True if we should start the process in
              the valgrind profiler.
          use_perftools_profiler: True if we should profile the process
              using perftools.
          use_tmux: True if we should start the process in tmux.
          stdout_file: A file handle opened for writing to redirect stdout to. If
              no redirection should happen, then this should be None.
          stderr_file: A file handle opened for writing to redirect stderr to. If
              no redirection should happen, then this should be None.
          pipe_stdin: If true, subprocess.PIPE will be passed to the process as
              stdin.
  
      Returns:
          Information about the process that was started including a handle to
              the process that was started.
      """
      # Detect which flags are set through environment variables.
      valgrind_env_var = f"RAY_{process_type.upper()}_VALGRIND"
      if os.environ.get(valgrind_env_var) == "1":
          logger.info(
              "Detected environment variable '%s'.", valgrind_env_var
          )
          use_valgrind = True
      valgrind_profiler_env_var = (
          f"RAY_{process_type.upper()}_VALGRIND_PROFILER"
      )
      if os.environ.get(valgrind_profiler_env_var) == "1":
          logger.info(
              "Detected environment variable '%s'.",
              valgrind_profiler_env_var,
          )
          use_valgrind_profiler = True
      perftools_profiler_env_var = (
          f"RAY_{process_type.upper()}_PERFTOOLS_PROFILER"
      )
      if os.environ.get(perftools_profiler_env_var) == "1":
          logger.info(
              "Detected environment variable '%s'.",
              perftools_profiler_env_var,
          )
          use_perftools_profiler = True
      tmux_env_var = f"RAY_{process_type.upper()}_TMUX"
      if os.environ.get(tmux_env_var) == "1":
          logger.info(
              "Detected environment variable '%s'.", tmux_env_var
          )
          use_tmux = True
      gdb_env_var = f"RAY_{process_type.upper()}_GDB"
      if os.environ.get(gdb_env_var) == "1":
          logger.info(
              "Detected environment variable '%s'.", gdb_env_var
          )
          use_gdb = True
      # Jemalloc memory profiling.
      if os.environ.get("LD_PRELOAD") is None:
          jemalloc_lib_path = os.environ.get(
              RAY_JEMALLOC_LIB_PATH, JEMALLOC_SO
          )
          jemalloc_conf = os.environ.get(RAY_JEMALLOC_CONF)
          jemalloc_comps = os.environ.get(RAY_JEMALLOC_PROFILE)
          jemalloc_comps = (
              [] if not jemalloc_comps else jemalloc_comps.split(",")
          )
          jemalloc_env_vars = propagate_jemalloc_env_var(
              jemalloc_path=jemalloc_lib_path,
              jemalloc_conf=jemalloc_conf,
              jemalloc_comps=jemalloc_comps,
              process_type=process_type,
          )
      else:
          jemalloc_env_vars = {}
  
      use_jemalloc_mem_profiler = "MALLOC_CONF" in jemalloc_env_vars
  
      if (
          sum(
              [
                  use_gdb,
                  use_valgrind,
                  use_valgrind_profiler,
                  use_perftools_profiler,
                  use_jemalloc_mem_profiler,
              ]
          )
          > 1
      ):
          raise ValueError(
              "At most one of the 'use_gdb', 'use_valgrind', "
              "'use_valgrind_profiler', 'use_perftools_profiler', "
              "and 'use_jemalloc_mem_profiler' flags can "
              "be used at a time."
          )
      if env_updates is None:
          env_updates = {}
      if not isinstance(env_updates, dict):
          raise ValueError(
              "The 'env_updates' argument must be a dictionary."
          )
  
      modified_env = os.environ.copy()
      modified_env.update(env_updates)
  
      if use_gdb:
          if not use_tmux:
              raise ValueError(
                  "If 'use_gdb' is true, then 'use_tmux' must be true as well."
              )
  
          # TODO(suquark): Any better temp file creation here?
          gdb_init_path = os.path.join(
              ray._private.utils.get_ray_temp_dir(),
              f"gdb_init_{process_type}_{time.time()}",
          )
          ray_process_path = command[0]
          ray_process_args = command[1:]
          run_args = " ".join(
              ["'{}'".format(arg) for arg in ray_process_args]
          )
          with open(gdb_init_path, "w") as gdb_init_file:
              gdb_init_file.write(f"run {run_args}")
          command = ["gdb", ray_process_path, "-x", gdb_init_path]
  
      if use_valgrind:
          command = [
              "valgrind",
              "--track-origins=yes",
              "--leak-check=full",
              "--show-leak-kinds=all",
              "--leak-check-heuristics=stdstring",
              "--error-exitcode=1",
          ] + command
  
      if use_valgrind_profiler:
          command = ["valgrind", "--tool=callgrind"] + command
  
      if use_perftools_profiler:
          modified_env["LD_PRELOAD"] = os.environ["PERFTOOLS_PATH"]
          modified_env["CPUPROFILE"] = os.environ["PERFTOOLS_LOGFILE"]
  
      modified_env.update(jemalloc_env_vars)
  
      if use_tmux:
          # The command has to be created exactly as below to ensure that it
          # works on all versions of tmux. (Tested with tmux 1.8-5, travis'
          # version, and tmux 2.1)
          command = [
              "tmux",
              "new-session",
              "-d",
              f"{' '.join(command)}",
          ]
  
      if fate_share:
          assert ray._private.utils.detect_fate_sharing_support(), (
              "kernel-level fate-sharing must only be specified if "
              "detect_fate_sharing_support() has returned True"
          )
  
      def preexec_fn():
          import signal
  
          signal.pthread_sigmask(signal.SIG_BLOCK, {signal.SIGINT})
          if fate_share and sys.platform.startswith("linux"):
              ray._private.utils.set_kill_on_parent_death_linux()
  
      win32_fate_sharing = fate_share and sys.platform == "win32"
      # With Windows fate-sharing, we need special care:
      # The process must be added to the job before it is allowed to execute.
      # Otherwise, there's a race condition: the process might spawn children
      # before the process itself is assigned to the job.
      # After that point, its children will not be added to the job anymore.
      CREATE_SUSPENDED = 0x00000004  # from Windows headers
      if sys.platform == "win32":
          # CreateProcess, which underlies Popen, is limited to
          # 32,767 characters, including the Unicode terminating null
          # character
          total_chrs = sum([len(x) for x in command])
          if total_chrs > 31766:
              raise ValueError(
                  f"command is limited to a total of 31767 characters, "
                  f"got {total_chrs}"
              )
  
      process = ConsolePopen(
          command,
          env=modified_env,
          cwd=cwd,
          stdout=stdout_file,
          stderr=stderr_file,
          stdin=subprocess.PIPE if pipe_stdin else None,
          preexec_fn=preexec_fn if sys.platform != "win32" else None,
          creationflags=CREATE_SUSPENDED if win32_fate_sharing else 0,
      )
  
      if win32_fate_sharing:
          try:
              ray._private.utils.set_kill_child_on_death_win32(process)
              psutil.Process(process.pid).resume()
          except (psutil.Error, OSError):
              process.kill()
              raise
  
      def _get_stream_name(stream):
          if stream is not None:
              try:
                  return stream.name
              except AttributeError:
                  return str(stream)
          return None
  
      return ProcessInfo(
          process=process,
          stdout_file=_get_stream_name(stdout_file),
          stderr_file=_get_stream_name(stderr_file),
          use_valgrind=use_valgrind,
          use_gdb=use_gdb,
          use_valgrind_profiler=use_valgrind_profiler,
          use_perftools_profiler=use_perftools_profiler,
          use_tmux=use_tmux,
      )
  
imports: import base64
  import collections
  import errno
  import io
  import json
  import logging
  import mmap
  import multiprocessing
  import os
  import random
  import shutil
  import signal
  import socket
  import subprocess
  import sys
  import time
  from pathlib import Path
  from typing import List, Optional, IO, AnyStr
  import psutil
  from filelock import FileLock
  import ray
  import ray._private.ray_constants
  from ray._raylet import GcsClient, GcsClientOptions
  from ray.core.generated.common_pb2 import Language
  from ray._private.ray_constants import RAY_NODE_IP_FILENAME
label_desc: Use image node_id 28 for calling a global function with example usage: start_ray_process(command, process_type, fate_share, env_updates, cwd, use_valgrind, use_gdb, use_valgrind_profiler, use_perftools_profiler, use_tmux, stdout_file, stderr_file, pipe_stdin) and returns: ProcessInfo, None, stream, str