code: function errorMsg (ppid, error, ctx, msg) {
      let contentFile = ".smappi-request-content-" + ppid,
          syncFile = ".smappi-request-sync-" + ppid;
      fs.writeFileSync(contentFile, JSON.stringify({err: error, ctx: ctx, message: msg}), 'utf8');
      fs.existsSync(syncFile) && fs.unlinkSync(syncFile);
  }
docs: ************************************************************************************  Worker starts (see "spawn" in smappi-cl/lib/request/index.js) as a separate process, so that while can not block the execution of the requester  Exchange data via the file "contentFile" Also there is a mutex for synchronization index.js and worker.js  ************************************************************************************