Derek Kwok

The command to use is:

du -hd 1 <directory>

For example, if I wanted to list the size of all directories in my home folder, I would use:

$ du -hd 1 ~
  0B	/Users/derekkwok/.Trash
 83M	/Users/derekkwok/.android
 56M	/Users/derekkwok/.bower
 96K	/Users/derekkwok/.dbvis
6.8M	/Users/derekkwok/.dropbox
  0B	/Users/derekkwok/.dvdcss
253M	/Users/derekkwok/.env

    ... snipped ...

 12K	/Users/derekkwok/Pictures
957M	/Users/derekkwok/Projects
  0B	/Users/derekkwok/Public
 20G	/Users/derekkwok

This command is also convenient in that it lists the total folder size also as the last entry.

I spent an hour today trying to debug the following code:

if self.zip:
    self.zip.storage.delete(self.zip.path)

    temp_zip_file = tempfile.NamedTemporaryFile(mode='w')
    temp_zip = zipfile.ZipFile(manga_zip_file.name, 'w')

    # write other files into temp_zip

    self.zip.save('', File(open(temp_zip_file.name)))

I spent a good chunk of time trying to figure out why the zip being saved is invalid. It turns out that I needed to add:

temp_zip.close() # this writes the zip file ending records, making this a valid zipfile

I should have read the [documentations](http://docs.python.org/2/library/zipfile) more closely!

I came across a very useful little snippet of JS today that counts the number of CSS rules and selectors you have.

function countCSSRules() {
    var results = '',
            log = '';
    if (!document.styleSheets) {
        return;
    }
    for (var i = 0; i < document.styleSheets.length; i++) {
        countSheet(document.styleSheets[i]);
    }
    function countSheet(sheet) {
        var count = 0;
        if (sheet && sheet.cssRules) {
            for (var j = 0, l = sheet.cssRules.length; j < l; j++) {
                if (!sheet.cssRules[j].selectorText) continue;
                count += sheet.cssRules[j].selectorText.split(',').length;
            }

            log += '\nFile: ' + (sheet.href ? sheet.href : 'inline <style> tag');
            log += '\nRules: ' + sheet.cssRules.length;
            log += '\nSelectors: ' + count;
            log += '\n--------------------------';            
        }
    }
    console.log(log);
    console.log(results);
};
countCSSRules();

Usually I place this script inside a <script> tag in my projects, which outputs the results to the browser console. This script is only loaded in development environments. Source: https://gist.github.com/psebborn/1885511

Source: http://superuser.com/questions/556179/unable-to-extract-mkv-attachments-with-ffmpeg In short, the command you should run is this:

ffmpeg -dump_attachment:t "" -i test.mkv

This dumps all the attachment files into your current working directory.

Source: http://news.ycombinator.com/item?id=4906942 Below is an organized list of placeholder sites mentioned in the comments section: * [Fake images please?](http://fakeimg.pl/) * [lorempixel](http://lorempixel.com/) * [Placehold.it](http://placehold.it/) * [{placekitten}](http://placekitten.com/) * [pugholder!](http://pugholder.com/) * [Dummy Images](http://www.dummyimages.com/) Leave a comment on any other image placeholder sites you use, and I will add them to this list.