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 0
  • 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?


    9
    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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Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Start a local web server in the current directory on a random dynamic port.

Get all mac address

alias to close terminal with :q
Put this in your ~/.bashrc file (or the equivalent) If you use vim a lot, this alias will be immediately obvious. Your brain will thank you.

Convert all WMF images to SVG recursively ignoring file extension case
This assumes you have the package installed necessary for converting WMF files. On my Ubuntu box, this is libwmf-bin. I used this command, as libwmf is not on my wife's iMac, so I archived the directories containing the WMF files from OS X, ran them on my Ubuntu box, archived the resulting SVGs, and sent them back to her. Quick, simple and to the point. Searches directories recursively looking for extensions ignoring case. This is much more readable and clean than -exec for find. The while loop also gives further flexibility on complex logic. Also, although there is 'wmf2svg --auto', it expects lowercase extensions, and not uppercase. Because I want to ignore case, I need to use the -o option instead. Works in ZSH and BASH. Haven't tested in other shells.

Get file access control list

Remove a line in a text file. Useful to fix "ssh host key change" warnings

Smart renaming
Use 'mmv' for mass renames. The globbing syntax is intuitive.

Read a tcpdump file and count SYN packets to port 80, Order column by destination.

diff will usually only take one file from STDIN. This is a method to take the result of two streams and compare with diff. The example I use to compare two iTunes libraries but it is generally applicable.
diff is designed to compare two files. You can also compare directories. In this form, bash uses 'process substitution' in place of a file as an input to diff. Each input to diff can be filtered as you choose. I use find and egrep to select the files to compare.


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