Qfyilyi

I am facing an issue wanting to kill a FFmpeg process triggered by spawn from the child_process native NodeJs package.

Here is the script i use to trigger the ffmpeg process.

Assume that the conversion takes a long time, like about 2 hours.

/**

 * Execute a command line cmd

 * with the arguments in options given as an array of string

 * processStore is an array that will store the process during its execution

 * and remove it at the end of the command or when error occurs

 */

function execCommandLine({

   cmd,

   options = ,

   processStore = ,

}) {

  return new Promise((resolve, reject) => {

    const spwaned_process = childProcess.spawn(cmd, options);



    // Append the process to a buffer to keep track on it

    processStore.push(spwaned_process);



    // Do nothing about stdout

    spwaned_process.stdout.on('data', () => true);



    // Do nothing about stderr

    spwaned_process.stderr.on('data', () => true);



    spwaned_process.on('close', () => {

      const index = processStore.indexOf(spwaned_process);



      if (index !== -1) {

        processStore.splice(index, 1);

      }



      resolve();

    });



    spwaned_process.on('error', () => {

      const index = processStore.indexOf(spwaned_process);



      if (index !== -1) {

        processStore.splice(index, 1);

      }



      reject();

    });

  });

}



const processStore = ;



await execCommandLine({

  cmd: 'ffmpeg',



  options: [

    '-i',

    '/path/to/input',

    '-c:v',

    'libvpx-vp9',

    '-strict',

    '-2',

    '-crf',

    '30',

    '-b:v',

    '0',

    '-vf',

    'scale=1920:1080',

    '/path/to/output',

  ],



  processStore,

});

During the conversion, the following code is called to kill all process into the processStore, including the FFmpeg process that is triggered.

// getProcessStore() returns the const processStore array of the above script

getProcessStore().forEach(x => x.kill());



process.exit();

After the program exit, when i run ps -ef | grep ffmpeg, there is still some FFmpeg process running.

root 198 1 0 09:26 ? 00:00:00 ffmpeg -i /path/to/input -ss 00:01:47 -vframes 1 /path/to/output

root 217 1 0 09:26 ? 00:00:00 ps -ef

Do you have an idea about the way to kill a ffmpeg process properly ?

As stated in the node.js documentation of subprocess.kill([signal]), the default sent signal is SIGTERM.

Ffmpeg do not terminature receiving SIGTERM as explained by @sashoalm in here.

Newer versions of ffmpeg don't use 'q' anymore, at least on Ubuntu
Oneiric, instead they say to press Ctrl+C to stop them. So with a
newer version you can simply use 'killall -INT' to send them SIGINT
instead of SIGTERM, and they should exit cleanly.

So call x.kill('SIGINT');