Commands by sonic (8)

  • From the manpage: man less -X or --no-init Disables sending the termcap initialization and deinitialization strings to the terminal. This is sometimes desirable if the deinitialization string does something unnecessary, like clearing the screen. Bonus: If you want to clear the screen after viewing a file this way that had sensitive information, hit or just type clear. Since is readily available, I don't know why less bothers to automatically clear. If you're viewing the file at all, chances are you want to see the output from it after you quit. Show Sample Output


    2
    less -X /var/log/insecure
    sonic · 2016-06-24 13:53:49 3
  • The original command is great, but I often want to prepend to every line. Show Sample Output


    1
    sed -i 's/^/ls -l /' output_files.txt
    sonic · 2013-10-07 15:12:53 0
  • Prints line numbers making it easier to see long lines that wrap in your terminal and extra line breaks at the end of a file. :set nu works too. Show Sample Output


    0
    :set number
    sonic · 2013-10-07 15:03:52 0
  • If /home/sonic/archive/ was a symlink to /backup/sonic/archive it would follow the links and give you the file listing. By default find will NOT follow symbolic links. The default behavior for the find command is to treat the symlinks as literal files. I discovered this when trying to write a script run via cron to delete files with a modification time older than X days. The easiest solution was to use: /usr/bin/find -L /home/sonic/archive -name '*gz' -type f -mtime +14 -exec rm '{}' \; Show Sample Output


    -1
    find -L /home/sonic/archive -name '*gz' -type f
    sonic · 2013-10-07 14:32:22 0
  • the advantage to doing it this way is that you can adjust the max depth to get more recursive results and run it on non GNU systems. It also won't print trailing slashes, which can easily be removed, but can be slightly annoying.. You could run: # for file in `find * -maxdepth 0 -type d`;do ls -d $file;done and in the ls -d part of the command you can put in whatever parameters you want to get things like permissions, time stamps, and ownership. Show Sample Output


    0
    find * -maxdepth 0 -type d
    sonic · 2013-02-25 21:10:49 1
  • just an alternative to setting the size, this allows you to scroll up and see your previous commands in a given session but when you logout the history is not saved. That's the only advantage to doing it this way.. Show Sample Output


    0
    export HISTFILE=/dev/null
    sonic · 2013-02-18 16:37:01 0
  • To ignore aspect ratio, run: for file in *; do convert $file -resize 800x600! resized-$file; done and all images will be exactly 800x600. Use your shell of choice.. This was done in BASH. Show Sample Output


    0
    for file in *; do convert $file -resize 800x600 resized-$file; done
    sonic · 2013-02-17 21:37:14 0
  • I couldn't find this on the site and it's a useful switch. Great for large files. Show Sample Output


    2
    wget -c or wget --continue
    sonic · 2013-02-17 21:12:00 0

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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Spy audio, it only records if detects a sound or noise
It find out the mic recording level at the moment of run the command and if a noise level is higher it starts to record an mp3 file. The resulting file will have only the sounds not the silences.

Add line number count as C-style comments
I often find the need to number enumerations and other lists when programming. With this command, create a new file called 'inputfile' with the text you want to number. Paste the contents of 'outputfile' back into your source file and fix the tabbing if necessary. You can also change this to output hex numbering by changing the "%02d" to "%02x". If you need to start at 0 replace "NR" with "NR-1". I adapted this from http://osxdaily.com/2010/05/20/easily-add-line-numbers-to-a-text-file/.

automatically ditch old versions in a conflict
This is not exactly a commandline, but a vim macro to automatically ditch the "old" version of a conflict when dealing with the naster

Getting a domain from url, ex: very nice to get url from squid access.log

Find
A lot of X applications accept --geometry parameter so that you can set application size and position. But how can you figure out the exact arguments for --geometry? Launch an application, resize and reposition its window as needed, then launch xwininfo in a terminal an click on the application window. You will see some useful window info including its geometry.

Easy way to scroll up und down to change to one of n last visited directories.
This alias is meant to append n (here is n=10) most recently used cd commands to the bottom of history file. This way you can easily change to one of previous visited directories simply by hitting 1-10 times arrow up key. Hint: You can make more aliases implying the same rule for any set of frequently used long and complex commands like: mkisof, rdesktop, gpg...

New command with the last argument of the previous command.

This allows you to find a string on a set of files recursivly
The -r is for recursive, -F for fixed strings, --include='*.txt' identifies you want all txt files to be search any wildcard will apply, then the string you are looking for and the final * to ensure you go through all files and folders within the folder you execute it.

Print a list of all hardlinks in the working directory, recursively
libpurple likes to hardlink files repeatedly. To ignore libpurple, use sed: | sed '/\.\/\.purple/d'


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