====================
download entire html

https://www.lifewire.com/uses-of-command-wget-2201085
use this:
wget -r -k -R "*.gz, *.tar" www.xxx




https://www.linuxjournal.com/content/downloading-entire-web-site-wget

wget \
     --recursive \
     --no-clobber \
     --page-requisites \
     --html-extension \
     --convert-links \
     --restrict-file-names=windows \
     --domains website.org \
     --no-parent \
         www.website.org/tutorials/html/
This command downloads the Web site www.website.org/tutorials/html/.

The options are:

--recursive: download the entire Web site.

--domains website.org: don't follow links outside website.org.

--no-parent: don't follow links outside the directory tutorials/html/.

--page-requisites: get all the elements that compose the page (images, CSS and so on).

--html-extension: save files with the .html extension.

--convert-links: convert links so that they work locally, off-line.

--restrict-file-names=windows: modify filenames so that they will work in Windows as well.

--no-clobber: don't overwrite any existing files (used in case the download is interrupted and resumed).


====================

https://superuser.com/questions/332347/how-can-i-convert-mp4-video-to-mp3-audio-with-ffmpeg
convert mp4 to mp3 command line on MacOS:
ffmpeg -i video.mp4 -vn audio.mp3

ffmpeg out.mp3 -i in.m4a -codec:a libmp3lame -qscale:a 1

Split mp3 to many files:
ffmpeg -i somefile.mp3 -f segment -segment_time 3 -c copy out%03d.mp3
	Where -segment_time is the amount of time you want per each file (in seconds).
	so if you have a total 10h43m = 640m, then you can set 64m each file and 4000s each file



also for Mp4
ffmpeg -i * -c:v libx264 -crf 22 -map 0 -segment_time 1 -g 1 -sc_threshold 0 -force_key_frames "expr:gte(t,n_forced*9)" -f segment output%03d.mp4



当开机进程卡住时，有个可以查看的是 - 磁盘是否满了
df -h，不是所有东西都在主分区里
dmesg 看看内核有没有问题