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 4
  • 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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remove lines which are longer than 255

A function to find the newest file of a set.
Usage example: $newest Desktop/* Replace "-nt" with "-ot" for oldest. Run $shopt -s dotglob first to include dotfiles.

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"

Sort file greater than a specified size in human readeable format including their path and typed by color, running from current directory
1. find file greater than 10 MB 2. direct it to xargs 3. xargs pass them as argument to ls

Know which modules are loaded on an Apache server
This let you know which modules has loaded the Apache server, very useful to know if the mod_rewrite is ready to use.

Mount windows share to the specified location including credentials
Replace IP address with yours IP.

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

Create a new file

Number of .... indicate how far down to cd
Use dots to cd down directories instead of having to remember all of the pesky back slashes! Better yet, works on even and odd number of dots! Now, just estimate how far down you want to traverse.

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"


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