message: Log stdout and stderr on calling an external synctex command.
diff: @@ -462,8 +462,23 @@ export class Locator {
  .replace(/%TEX%/g, texFile)
  })
  }
  - this.extension.logger.addLogMessage(`Execute external SyncTeX command: command ${command}, args ${args}`)
  - cp.spawn(command, args)
  this.extension.logger.addLogMessage(`Open external viewer for syncTeX from ${pdfFile}`)
  + this.extension.logger.addLogMessage(`Execute external SyncTeX command: ${command}`)
  + this.extension.logger.addLogMessage(`Execute external SyncTeX args: ${JSON.stringify(args)}`)
  + const proc = cp.spawn(command, args)
  + let stdout = ''
  + proc.stdout.on('data', newStdout => {
  + stdout += newStdout
  + })
  + let stderr = ''
  + proc.stderr.on('data', newStderr => {
  + stderr += newStderr
  + })
  + const cb = () => {
  + void this.extension.logger.addLogMessage(`The external SyncTeX command stdout: ${stdout}`)
  + void this.extension.logger.addLogMessage(`The external SyncTeX command stderr: ${stderr}`)
  + }
  + proc.on('error', cb)
  + proc.on('exit', cb)
  }
  }
  