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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Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

List out classes in of all htmls in directory
Lists out all classes used in all *.html files in the currect directory. usefull for checking if you have left out any style definitions, or accidentally given a different name than you intended. ( I have an ugly habit of accidentally substituting camelCase instead of using under_scores: i would name soemthing counterBox instead of counter_box) WARNING: assumes you give classnames in between double quotes, and that you apply only one class per element.

Add all unversioned files to svn

Open a file in a GTK+ dialog window
I use zenity because it's a rewrite of gdialog and also replaces gmessage and has more useful options. Using --text-info allows you to select and copy the text to your clipboard. To see a file in a list dialog: cat /etc/passwd | zenity --width 800 --height 600 --list --column Entries If you don't have zenity, you'll have to download it via apt-get install zenity, etc.

use jq to validate and pretty-print json output
the `jq` tool can also be used do validate json files and pretty print output `cat file.json | jq` available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/

Google URL shortener
Use curl and sed to shorten an URL using goo.gl without any other api

yum -q list updates | tail -n+2

Find the package that installed a command

Fix for error perl: warning: Setting locale failed.
Fix for ubuntu error: perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LANGUAGE = "en_GB:en", LC_ALL = (unset), LANG = "en_GB.UTF-8" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). locale: Cannot set LC_CTYPE to default locale: No such file or directory locale: Cannot set LC_MESSAGES to default locale: No such file or directory locale: Cannot set LC_ALL to default locale: No such file or directory

Execute a file in vim with the #!/bin/interpreter in the first line


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