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Create a video screencast of any x11 window, with audio
The script gets the dimensions and position of a window and calls ffmpeg to record audio and video of that window. It saves it to a file named output.mkv

Debug pytest failures in the terminal
pudb is an ncurses debugger. This command will allow interactive debugging of test failures in pytest using pudb.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

find external links in all html files in a directory list
Just a handy way to get all the unique links from inside all the html files inside a directory. Can be handy on scripts etc.

Print just line 4 from a textfile
this method should be the fastest

Netstat Connection Check
This command does a tally of concurrent active connections from single IPs and prints out those IPs that have the most active concurrent connections. VERY useful in determining the source of a DoS or DDoS attack.

ps a process keeping the header info so you know what the columns of numbers mean!
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 1828 0.0 0.0 5396 476 ? Ss 2008 0:00 /usr/sbin/sshd

Efficient count files in directory (no recursion)
$ time perl -e 'if(opendir D,"."){@a=readdir D;print $#a - 1,"\n"}' 205413 real 0m0.497s user 0m0.220s sys 0m0.268s $ time { ls |wc -l; } 205413 real 0m3.776s user 0m3.340s sys 0m0.424s ********* ** EDIT: turns out this perl liner is mostly masturbation. this is slightly faster: $ find . -maxdepth 1 | wc -l sh-3.2$ time { find . -maxdepth 1|wc -l; } 205414 real 0m0.456s user 0m0.116s sys 0m0.328s ** EDIT: now a slightly faster perl version $ perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' sh-3.2$ time perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' 205414 real 0m0.415s user 0m0.176s sys 0m0.232s

1+2-3+4-5+6-7 Series

Optimal way of deleting huge numbers of files


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