class_docstr: Executes *nproc* tasks in parallel after forking.
class_docstr_tok: ["Executes","*","nproc","*","tasks","in","parallel","after","forking","."]
code: def _join_one(self) -> bool:
      joined_any = False
      for tid, pipe in self._precvs.items():
          if pipe.poll():
              exc, logs, result = pipe.recv()
              if exc:
                  raise SphinxParallelError(*result)
              for log in logs:
                  logger.handle(log)
              self._result_funcs.pop(tid)(self._args.pop(tid), result)
              self._procs[tid].join()
              self._precvs.pop(tid)
              self._pworking -= 1
              joined_any = True
              break
  
      while self._precvsWaiting and self._pworking < self.nproc:
          newtid, newprecv = self._precvsWaiting.popitem()
          self._precvs[newtid] = newprecv
          self._procs[newtid].start()
          self._pworking += 1
  
      return joined_any
  
file_path: sphinx/sphinx/util/parallel.py
imports: from __future__ import annotations
  import os
  import time
  import traceback
  from math import sqrt
  from typing import TYPE_CHECKING, Any, Callable
  from sphinx.errors import SphinxParallelError
  from sphinx.util import logging
label_desc: Use image node_id 6 for calling the ParallelTasks obj's underlying member method code with example usage: obj._join_one() and returns: joined_any