Commands by TetsuyO (5)

  • Finds files modified today since 00:00, removes ugly dotslash characters in front of every filename, and sorts them. *EDITED* with the advices coming from flatcap (thanks!)


    -2
    find -maxdepth 1 -type f -newermt "00:00" -printf "%f\n" | sort
    TetsuyO · 2013-03-23 12:50:01 8
  • This oneliner gets all the 'modified' files in your git repository, and opens all of them in vim. Very handy when you're starting to work in the morning and you simply want to review your modified files before committing them. Maybe there are better ways to do that (and maybe integrated in vim and/or git, who knows), but I found quicker to do this oneliner.


    0
    vim `git status | grep modified | awk '{print $3}'`
    TetsuyO · 2012-11-19 09:48:46 6
  • Substitute that 724349691704 with an UPC of a CD you have at hand, and (hopefully) this oneliner should return the $Artist - $Title, querying discogs.com. Yes, I know, all that head/tail/grep crap can be improved with a single sed command, feel free to send "patches" :D Enjoy! Show Sample Output


    -1
    wget http://www.discogs.com/search?q=724349691704 -O foobar &> /dev/null ; grep \/release\/ foobar | head -2 | tail -1 | sed -e 's/^<div>.*>\(.*\)<\/a><\/div>/\1/' ; rm foobar
    TetsuyO · 2011-01-30 23:34:54 3
  • This is an example of the usage of pdfnup (you can find it in the 'pdfjam' package). With this command you can save ink/toner and paper (and thus trees!) when you print a pdf. This tools are very configurable, and you can make also 2x2, 3x2, 2x3 layouts, and more (the limit is your fantasy and the resolution of the printer :-) You must have installed pdfjam, pdflatex, and the LaTeX pdfpages package in your box. Show Sample Output


    3
    pdfnup --nup 2x1 --frame true --landscape --outfile output.pdf input.pdf
    TetsuyO · 2010-12-21 14:20:06 5
  • Quick and dirty version. I made a version that checks if a manpage exists (but it's not a oneliner). You must have ps2pdf and of course Ghostscript installed in your box. Enhancements appreciated :-)


    59
    man -t manpage | ps2pdf - filename.pdf
    TetsuyO · 2010-12-19 22:40:18 15

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New command with the last argument of the previous command.

Multi-thread any command
For instance: $ find . -type f -name '*.wav' -print0 |xargs -0 -P 3 -n 1 flac -V8 will encode all .wav files into FLAC in parallel. Explanation of xargs flags: -P [max-procs]: Max number of invocations to run at once. Set to 0 to run all at once [potentially dangerous re: excessive RAM usage]. -n [max-args]: Max number of arguments from the list to send to each invocation. -0: Stdin is a null-terminated list. I use xargs to build parallel-processing frameworks into my scripts like the one here: http://pastebin.com/1GvcifYa

count the number of specific characters in a file or text stream
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 :)

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Fix "broken" ID3 tags in the current directory and subdirectories
Some MP3s come with tags that don't work with all players. Also, some good tag editors like, EasyTAG output tags that don't work with all players. For example, EasyTAG saves the genre as a numeric field, which is not used correctly in Sansa MP3 players. This command corrects the ID3 tags in MP3 files using mid3iconv, which comes with mutagen. To install Mutagen on Fedora use "yum install python-mutagen"

Factory reset your harddrive. (BE CAREFUL!)

add a backup (or any other) suffix to a file
Very helpful when you've got complex filenames and needs to change just some small parts of it. Renaming a file called "i-made-a-small-typo-right-here" to "i-made-a-big-typo-right-here": $ mv -vi i-made-a-{small,big}-typo-right-here You could also copy multiple files, edit, remove, process, etc.

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"

Go to parent directory of filename edited in last command

Convert JSON to YAML (unicode safe)
If you tried the other Python version of Convert JSON to YAML and you end up with lines that has "!!python/unicode", this version of the command is for you.


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