Commands by kyle0r (4)

  • In this example, where the users gpg keyring has a password, the user will be interactively prompted for the keyring password. If the keyring has no password, same as above, sans the prompt. Suitable for cron jobs. ~/.gnupg/passwd/http-auth.gpg is the encrypted http auth password, for this particular wget use case. This approach has many use cases. example bash functions: function http_auth_pass() { gpg2 --decrypt ~/.gnupg/passwd/http-auth.gpg 2>/dev/null; } function decrypt_pass() { gpg2 --decrypt ~/.gnupg/passwd/"$1" 2>/dev/null; }


    1
    wget --input-file=~/donwloads.txt --user="$USER" --password="$(gpg2 --decrypt ~/.gnupg/passwd/http-auth.gpg 2>/dev/null)"
    kyle0r · 2012-12-13 00:14:55 1
  • From the cwd, recursively find all rar files, extracting each rar into the directory where it was found, rather than cwd. A nice time saver if you've used wget or similar to mirror something, where each sub dir contains an rar archive. Its likely this can be tuned to work with multi-part archives where all parts use ambiguous .rar extensions but I didn't test this. Perhaps unrar would handle this gracefully anyway?


    10
    find . -name '*.rar' -execdir unrar e {} \;
    kyle0r · 2012-09-27 02:27:03 0
  • the find -printf "%f\n" prints just the file name from the given path. This means directory paths which contain extensions will not be considered. Show Sample Output


    0
    find /some/path -type f -and -printf "%f\n" | egrep -io '\.[^.]*$' | sort | uniq -c | sort -rn
    kyle0r · 2012-04-02 19:25:35 0
  • In this example, the command will recursively find files (-type f) under /some/path, where the path ends in .mp3, case insensitive (-iregex). It will then output a single line of output (-print0), with results terminated by a the null character (octal 000). Suitable for piping to xargs -0. This type of output avoids issues with garbage in paths, like unclosed quotes. The tr command then strips away everything but the null chars, finally piping to wc -c, to get a character count. I have found this very useful, to verify one is getting the right number of before you actually process the results through xargs or similar. Yes, one can issue the find without the -print0 and use wc -l, however if you want to be 1000% sure your find command is giving you the expected number of results, this is a simple way to check. The approach can be made in to a function and then included in .bashrc or similar. e.g. count_chars() { tr -d -c "$1" | wc -c; } In this form it provides a versatile character counter of text streams :) Show Sample Output


    1
    find /some/path -type f -and -iregex '.*\.mp3$' -and -print0 | tr -d -c '\000' |wc -c
    kyle0r · 2012-03-31 21:57:33 0

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Find which service was used by which port number

Create the oauth token required for a Twitter stream feed
This is the THIRD in a set of five commands. See my other commands for the previous two. This step creates the oauth 1.0 token as explained in http://oauth.net/core/1.0/ The token is required for a Twitter filtered stream feed (and almost all Twitter API calls) This token is simply an encrypted version of your base string. The encryption key used is your hmac. The last part of the command scans the Base64 token string for '+', '/', and '=' characters and converts them to percentage-hex escape codes. (URI-escapeing). This is also a good example of where the $() syntax of Bash command substitution fails, while the backtick form ` works - the right parenthesis in the case statement causes a syntax error if you try to use the $() syntax here. See my previous two commands step1 and step2 to see how the base string variable $b and hmac variable $hmac are generated.

Get http headers for an url

List just the executable files (or directories) in current directory
A bit shorter ;)

Set random background image in gnome
Changes your desktop background image in gnome. Update the directory to wherever you keep your wallpapers. I like to create a sub-directory in my Wallpaper folder called "cycle" that I use to define the wallpapers I wish to loop in cron. ex: $ gconftool-2 -t str -s /desktop/gnome/background/picture_filename "$(find ~/Wallpapers/cycle -type f | shuf -n1)"

Display network pc "name" and "workgroup"
Checks for PC samba name and workgroup. Works fine for Windows hosts and Linux/UNIX PCs running Samba.

Use Vim to convert text to HTML.
``vimhtml somefile.txt`` will open vim for the HTML convertion and close it immediately after its done, leaving you with somefile.html which you can later use in your website or whatever.

wrap long lines of a text
wraps text lines at the specified width (90 here). -s option is to force to wrap on blank characters -b count bytes instead of columns

Use the builtin ':' bash command to increment variables
I just found another use for the builtin ':' bash command. It increments counters for me in a loop if a certain condition is met... : [arguments] No effect; the command does nothing beyond expanding arguments and performing any specified redirections. A zero exit code is returned.

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.


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