Commands by jonty (6)

  • Use vi commands to edit your command lines

    If you spend all day editing in vi then switching your fingers to Emacs mode just for the command line can be difficult. Use set -o vi in your bash shell and enjoy the power of a real editor.


    1
    set -o vi; ls -l jnuk<ESC>bCjunk
    jonty · 2009-02-05 22:58:51 49
  • The simplest way to transport information over a network

    Einstein's razor: As simple as possible, but not simpler. On the destination machine netcat listens on any port (1234 in the example) and sends anything it receives into a file or pipe. On the source machine a separate netcat takes input from a file or pipe and sends it over the network to the listener. This is great between machines on a LAN where you don't care about authentication, encryption, or compression and I would recommend it for being simpler than anything else in this situation. Over the internet you should use something with better security.


    3
    (on destination machine) nc -l 1234 > whatever; (on source machine) nc destination 1234 < whatever;
    jonty · 2009-02-05 21:35:08 17
  • Getting started with tcpdump

    At some point you want to know what packets are flowing on your network. Use tcpdump for this. The man page is obtuse, to say the least, so here are some simple commands to get you started. -n means show IP numbers and don't try to translate them to names. -l means write a line as soon as it is ready. -i eth0 means trace the packets flowing through the first ethernet interface. src or dst w.x.y.z traces only packets going to or from IP address w.x.y.z. port 80 traces only packets for HTTP. proto udp traces only packets for UDP protocol. Once you are happy with each option combine them with 'and' 'or' 'not' to get the effects you want.


    2
    tcpdump -nli eth0; tcpdump -nli eth0 src or dst w.x.y.z; tcpdump -nli eth0 port 80; tcpdump -nli eth0 proto udp
    jonty · 2009-02-05 17:41:55 17
  • Start a new command in a new screen window

    If you are already running screen then you often want to start a command in a fresh window. You use this alias by typing 's whatever' from your command line and 'whatever' starts running in a new window. Good with interactive commands like info, vim, and nethack.


    19
    alias s='screen -X screen'; s top; s vi; s man ls;
    jonty · 2009-02-05 13:47:14 39
  • Get me yesterday's date, even if today is 1-Mar-2008 and yesterday was 29-Feb-2008

    Fool date by setting the timezone out by 24 hours and you get yesterday's date. Try TZ=XYZ-24 to get tomorrow's date. I live in TZ=GMT0BST so you might need to shift the number 24 by the hours in your timezone.


    1
    TZ=XYZ24 date
    jonty · 2009-02-05 13:27:14 26
  • Link all the files in this directory to that directory

    I find this handy for linking all the bin files in a package to /usr/bin or all the man files to /usr/share/man. You can replace * with */* to operate on all the files in subdirectories.


    0
    cd /this/directory; for f in *; do ln -s `pwd`/$f /that/directory; done
    jonty · 2009-02-05 13:21:16 48

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Silently deletes lines containing a specific string in a bunch of files
This command will find all occurrences of one or more patterns in a collection of files and will delete every line matching the patterns in every file

Rip a video for archiving, from any site
Download video files from a bunch of sites (here is a list https://rg3.github.io/youtube-dl/supportedsites.html). The options say: base filename on title, ignores errors and continue partial downloads. Also, stores some metadata into a .json file plz. Paste youtube users and playlists for extra fun. Protip: git-annex loves these files

List docker volumes by container

Open files in a split windowed Vim
-o acts like :spit. Use -O (capital o) for side-by-side like :vsplit. Use vim -d or vimdiff if you need a diff(1) comparison. To split gnu Screen instead of vim, use ^A S for horizontal, ^A | for vertical.

Ring the system bell after finishing a long script/compile
This will ring the system bell once if your script exits successfully and twice if it fails. So you can go look at something else and it will alert you when done. Don't forget to use 'xset b [vol [pitch [duration]]]' to get the bell to sound the way you want.

Url Encode
Returns URL Encoded string from input ($1).

Tells the shell you are using

generate random tone

Open a man page as a PDF in Gnome
Would be better if gnome-open would accept std in Should be doable in KDE - anyone?

bash pause command
Waiting for a key stroke. You can use this with a ";" behind to build a command chain.

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