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Kirsle.net http://www.kirsle.net/ The web blog of Kirsle en Copyright 2012, Kirsle.net Thu, 17 May 2012 12:52:12 GMT Thu, 17 May 2012 12:52:12 GMT root@kirsle.net Kirsle.net http://www.kirsle.net/static/avatars/casey.png http://www.kirsle.net/ 96 96 Kirsle's Avatar Unix Permissions on Folders http://www.kirsle.net/blog/kirsle/unix-permissions-on-folders Unix permissions become somewhat of a tricky thing when they're applied to directories instead of files. This post should hopefully clear up any confusion about them (they had me pretty confused so I figured them out by trial-and-error). On normal files, the permissions are pretty straightforward: <ul> <li>Read allows you to read the contents of the file (i.e. open a text file in an editor, open an image in a viewer).</li> <li>Write allows you to write to a file (make changes and save it, copy a new file over top of an old one, etc.)</li> <li>Execute allows you to run the file as a program (for a binary or e.g. a Perl script).</li> </ul> On directories, the permissions get a bit trickier. <ul> <li>Read allows you to list the contents of the directory to see the files inside. This is it. It doesn't implicitly allow you to read the contents of the files, or to descend into subdirectories. It only lists them.</li> <li>Write allows you to create new files in the directory or delete existing ones (even if the files belong to a different user, like root, that you wouldn't think you'd be able to delete). This only works if the Execute bit is also on.</li> <li>Execute allows you to interact with a file, or to traverse past the directory into a subdirectory (provided that subdirectory has permissions that allow you to do so). Basically, the Execute permission allows the permissions on the file or subdirectory to take effect. If the folder doesn't have Execute permissions, any attempt to do anything to a file or subdirectory is automatically denied.</li> </ul> So here's a breakdown of the different permission combinations and what they do for you: <ul> <li>--- (000): No permissions. Can't open the folder, list its contents, or do anything with its contents.</li> <li>r-- (400): You can list the contents. You can't open the files, or descend into subdirectories. Can't create new files or write to existing ones.</li> <li>-w- (200): This is the same as ---, or, no permissions at all. The write permission is useless without Execute.</li> <li>--e (100): You can't list the contents of the folder, but if you know of a specific name of a file or subdirectory, you can interact with it (provided it has permissions that allow you to). You can <code>cd</code> into a subdirectory or read/write a file that has permissions for it. But no listing the directory's contents.</li> <li>rw- (600): Same as r--, you can list the contents but nothing more. The Write permission is useless without Execute. <li>r-e (500): You can list the contents, access files (subject to their permissions), and descend into subdirectories (subject to their permissions). You can't create new files though.</li> <li>-we (300): This one is interesting. You can not list the contents of the directory, but you can interact with existing files (if you know their names in advance), and you can create new files in the directory and delete existing files. You can also descend into subdirectories.</li> <li>rwx (700): All permissions for the directory.</li> </ul> Fri, 4 May 2012 23:09:31 GMT Firefox Nightly http://www.kirsle.net/blog/kirsle/firefox-nightly If anyone's interested, I wrote a Perl script that downloads and installs Firefox Nightly on a Unix-like operating system. By default, it installs the application into <code>/opt/firefox-nightly</code>, with a link to run it at <code>/usr/bin/firefox-nightly</code>. This way, it doesn't conflict with your already-installed version of Firefox. Furthermore, it will put a launcher item in your Applications/Internet menu. You can get it from here: <a href="http://sh.kirsle.net/ffnightly">http://sh.kirsle.net/ffnightly</a> <pre>$ mkdir ~/bin $ wget http://sh.kirsle.net/ffnightly -O bin/ffnightly $ chmod +x bin/ffnightly $ ffnightly</pre> Mon, 23 Apr 2012 02:01:10 GMT Gnome Predictions http://www.kirsle.net/blog/kirsle/gnome-predictions I have a couple of rather cynical predictions about what new problems <a href="/blog/kirsle/category/Gnome%203">Gnome 3</a> could bring to Linux (or Fedora, in particular) that I feel like writing down here just so I can say "I told you so!" as I begrudgingly look into installing Arch Linux on all my computers at some point in the future. [image] <ul> <li>Obsoleting of the Gnome Sound Applet: this one seems very likely to happen within the next couple releases of Fedora. The <code>gnome-sound-applet</code> isn't very useful in the Gnome Shell desktop environment, because the Shell has its own built-in volume control icon on the top panel. The reason it's still around is probably just for the Gnome 3 fall-back desktop, where you get a two-panel layout similar to Gnome 2, which still has a decent system tray on the top panel. For Gnome 3 users without hardware acceleration, the gnome-sound-applet comes to the rescue to let these users continue adjusting their sound volume. But, with <a href="https://fedoraproject.org/wiki/Features/Gnome_shell_software_rendering">Gnome Shell software rendering</a> coming in Fedora 17, the need to maintain the system tray sound applet will quickly vanish, since even Gnome 3 users without hardware acceleration will be seeing the same shell desktop with its own built-in sound applet. This sucks a lot for XFCE and other desktop users. One of my favorite things about the Gnome sound applet is the ability to increase the volume higher than 100%, which XFCE's clunky old sound mixer applet still can't do.</li> <li>Obsoleting of the Network Manager applet: I strongly hope not. But at the same time I could see this being something the Gnome developers would consider seriously. The argument would probably go a little something like this: "There are currently hacks in place in Gnome Shell that allows us to run the NetworkManager applet, but place its icon in the shell panel instead of the normal system tray. So, it makes sense to just program the NetworkManager to go directly to the Gnome panel instead, and no longer support the system tray version anymore. This is good for Gnome, and anybody using XFCE or some other desktop that will have objections to this change, well they can just switch to some other distro. We don't care." On this one, I hope I'm wrong. [image] But due to Gnome's short-sightedness with some of their recent design decisions (<a href="/blog/kirsle/zenity-and-gnome-3">ruining Zenity, anyone?</a>) I wouldn't be shocked to see them come up with such an idea.</li> </ul> So, there they are. Obsoleting the sound applet? Very likely. The NetworkManager? I really don't know how likely they are to do this, but this would probably be the thing that finally pushes me to abandon Fedora entirely. Fri, 13 Apr 2012 23:39:05 GMT Turn off monitor from Linux CLI http://www.kirsle.net/blog/kirsle/turn-off-monitor-from-linux-cli I keep looking up this information and then losing track of it, so I'm posting it here for my own reference. This command will turn off the monitor on a Linux box from the command line (sorta like what happens when you have your power saving options configured to do this automatically after a length of time): <pre>xset dpms force off</pre> The monitor turns off until you hit a keyboard button or move the mouse. With this info you could set up a keyboard shortcut to run this command and have something like a "lock screen button" on your netbook, to turn off the display on command and conserve battery life for a little bit longer than usual. For a "lock screen button" that also locks the screen in addition to turning it off, a pair of commands like this may be handy: <pre>xset dpms force off; xscreensaver-command --lock</pre> Wed, 21 Mar 2012 17:31:37 GMT Install Chromium OS Lime http://www.kirsle.net/blog/kirsle/install-chromium-os-lime This information is ridiculously hard to find on the Internet. I was playing with Chromium OS using the Lime build provided by <a href="http://chromeos.hexxeh.net/">Hexxeh</a>. The Lime build is the same as the Vanilla build (i.e. upstream Chromium source code built daily), but it has more driver support, and it's the only build that works with the wifi on my Dell Mini 9. Getting it onto a flash drive and booting from it was easy enough just following the directions on Hexxeh's site, but actually installing it to the hard drive was a bit more difficult. It was hard to find any up-to-date information online; most bloggers were talking about Hexxeh's old "Flow" builds, so the instructions were outdated. When I specifically googled how to install the Lime build, I was still finding outdated instructions. Everyone was saying that you just hit <code>Ctrl-Alt-T</code> to get a shell prompt, and run the <code>install</code> command. Not that easy. The only way I could get into any form of text mode was by hitting <code>Ctrl-Alt-F2</code> (which I only knew to try because I'm a Linux user). But this got me into a text mode login prompt and it took me a while to figure out the right username/password combination. The username is <code>chronos</code> and the password is <code>facepunch</code>. After that, I was stuck in a really primitive shell that doesn't support anything I'm used to (not even <code>ls</code>), so I went out on a limb and tried running the command <code>bash</code> (which got me into a more familiar Bash shell). But the <code>install</code> command was no good in Bash -- it was running the GNU install command instead of the one to install Chromium to the disk. After some more tinkering, I found that if I ran <code>crosh</code> (Chrome shell) and then run the install command from there, it did what I want. So, I was finally able to install it to disk. It didn't end up working out though. The system doesn't boot after installation. Oh well. But hopefully this blog post will help others find out how to install the darn thing. tl;dr: here's how I figured out to install Chromium OS to disk: <ol> <li>Boot it from the USB drive.</li> <li>Push Ctrl-Alt-F2 to get to the text mode login.</li> <li>Log in as <code>chronos</code> / <code>facepunch</code></li> <li>Type <code>crosh</code>, hit enter.</li> <li>Type <code>install</code>, hit enter.</li> </ol> Update (Mar 6): It turns out Dell has their own semi-official builds of Chromium OS for the Dell Mini 9 and 10v laptops. They can be downloaded from <a href="http://linux.dell.com/files/cto/">Dell's site here</a>. I downloaded the Jan 3 2012 image. Following their instructions was easy enough, but I found a few differences that I'll note here: <ul> <li>On the first boot from the USB, wifi drivers weren't installed, so I couldn't get past the first screen. <code>Ctrl-Alt-T</code> doesn't work here, so I had to use <code>Ctrl-Alt-F2</code> to get to the text mode login prompt.</li> <li>The text mode log-on is <code>chronos</code> / <code>dell1234</code> (the "dell" user didn't work). Then I was able to start <code>bash</code> and then execute <code>/etc/install_wl.sh</code> to install the wifi.</li> <li>On the second boot from USB, wifi worked and I went through the setup process. Once logged in, <code>Ctrl-Alt-T</code> works. [image]</li> </ul> The <code>install</code> from Dell's image did the trick too, and I now have Chromium installed on the internal hard drive on my Dell Mini 9. [image] Interestingly, the UI of Dell's image looks different to the Lime and Vanilla builds. The Lime and Vanilla builds had what looked like a sort of primitive desktop (complete with a wallpaper), and the Chromium browser windows could be resized and moved around the screen. Where you'd expect the task bar to be on a Windows system, was what looked more like the Mac dock, with icons representing all your opened Chromium windows (plus a couple other icons, one that brings up a menu and one that has the Chromium icon and didn't appear to do anything). Screenshots of UI differences: <a href="/creativity/articles/chromium-lime.png">[image]</a> Chromium Lime (and Vanilla) <a href="/creativity/articles/chromium-dell.png">[image]</a> Dell's Chromium build Dell's build looks more like the Chrome OS I've always seen screenshots of, so I think maybe the Lime and Vanilla builds are customized a bit (or else it's just a super new UI change and Dell's January image isn't up-to-date enough). Tue, 6 Mar 2012 04:06:15 GMT Video Thumbnails on Fedora XFCE http://www.kirsle.net/blog/kirsle/video-thumbnails-on-fedora-xfce This post is mostly for my own reference but if Google sends anybody here, hopefully it'll help them too. tl;dr version: it seems that the <code>gstreamer-ffmpeg</code> package is required for Thunar (or tumblerd, specifically) to render thumbnails of video files on the XFCE desktop for Fedora 16. This package is provided by <a href="http://rpmfusion.org">RPM Fusion</a> yum repository (<code>rpmfusion-free-updates</code> specifically). It seems to be pretty hard to find this information online. None of my Fedora XFCE systems were able to render thumbnails of videos, and this caused me some headaches with removable drives (when I'd be done with the drive and want to unmount it, I wouldn't be able to because "the device is still busy"... and <code>lsof /media/Cyro</code> would show that tumblerd was the culprit... it was trying to render thumbnails of any video files I may have seen while browsing in Thunar and wasn't having much luck with it). The usual set of packages that provide all the video codecs for me didn't do the job (vlc, smplayer, gstreamer-plugins-{good,bad,ugly}), I even tried installing ffmpegthumbnailer and no luck. Finally I installed gstreamer-ffmpeg, and after doing a <code>killall thumblerd</code> and then visiting a folder full of videos in Thunar, it finally worked and started making thumbnails. Fri, 10 Feb 2012 18:29:29 GMT Force MSN Messenger to Use a Proxy http://www.kirsle.net/blog/kirsle/force-msn-messenger-to-use-a-proxy For anybody wanting to know how to do this, it's possible to force Windows Live Messenger to obey your proxy settings. In my case I wanted MSN 2011 to connect using a socks proxy (using <a href="/blog/kirsle/ssh-port-forwarding">SSH port forwarding</a> to use an SSH tunnel as SOCKS 5 proxy). To set the proxy settings, go to the "Connection" page in the preferences of MSN Messenger, click Advanced Settings and enter your proxy details. The problem is, MSN will only use your proxy settings if it can't normally connect to MSN without them (i.e. if your default TCP internet connection will work, MSN will always use that instead of your proxy settings). This is how you can force MSN to use the proxy settings. You have to block MSN from being able to connect to its authentication servers without the proxy. To do this, we have to tamper with the <a href="http://en.wikipedia.org/wiki/Hosts_%28file%29">Hosts file</a>. The Hosts file on Windows is kept at <code>C:\Windows\System32\drivers\etc\hosts</code> (note that it doesn't have a file extension). Open this in a text editor like Notepad or the <code>edit</code> command in Command Prompt (I prefer the latter approach because you can open a Command Prompt window as Administrator and then editing the file is a snap without having to deal with permission issues when saving changes). Add these lines to the Hosts file: <pre>127.0.0.1 messenger.hotmail.com 127.0.0.1 msgr.hotmail.com 127.0.0.1 gateway.messenger.hotmail.com 127.0.0.1 login.gateway.hotmail.com</pre> And then restart MSN and it should have difficulty connecting without the proxy settings (if using a SOCKS proxy, attempt to sign into MSN before you open the proxy to be sure that it fails to connect. Then start the proxy and see that it successfully signs in). This works by routing all the MSN Messenger hostnames to the loopback address and blocks MSN from being able to authenticate. But with the SOCKS proxy, it can connect because it would do the DNS lookups from the SSH server instead of the local system. Hope this helps someone! Fri, 30 Dec 2011 22:33:45 GMT VirtualBox Scale Mode http://www.kirsle.net/blog/kirsle/virtualbox-scale-mode Updated: added pictures. Bumped the timestamp to make this post new again. I don't know how I missed this, but apparently <a href="http://www.virtualbox.org/">VirtualBox</a> finally supports a "Scale Mode." I've always wanted this feature. Why, you ask? One easy example is for running an old operating system (older than Windows 2000) that isn't supported by VirtualBox, so that there are no Guest Additions for it. Guest Additions for supported OS's install extra drivers for the virtual machine, so that when you put VirtualBox into "Full Screen" mode, the guest OS will automatically increase its screen resolution to fit your display. When it can't do that, it will just display the screen at its literal resolution and put a black margin to fill in the extra space. Here is an expertly Photoshopped demonstration of what I'm talking about. If you were running a Windows 3.1 virtual machine at an 800x600 screen resolution, and you put the VM full-screen, this is what it would look like on your 1366x768 monitor: [image] Another example: even on supported guests, running an older game like Starcraft (which runs in a resolution of 640x480) had this problem too: if the VM is running Full Screen and you start Starcraft... instead of the game's display stretching across your whole monitor, it stays at 640x480 pixels and is centered on the screen. This sucks. So it seems VirtualBox has finally added Scale Mode (available in the "Machine" menu along side Full Screen and Seamless modes). There's one quirk to it, though: Scale Mode and Full Screen don't work together. On my system, going into Scale Mode put the virtual machine into a window on my screen. This window could be maximized, but it couldn't be made full screen. So that sorta sucks. Luckily, my Linux window manager (xfwm4, the window manager of the <a href="http://xfce.org/">XFCE desktop environment</a>) supports putting any window full screen, whether the window wants it or not. This means the window decorations are taken away and the contents of the window are resized to fill the display. Success! I can now run full screen, scaled resolution guest operating systems. [image] [image] Scale mode with xfwm4's full-screen option gives you a "native" experience. Sat, 17 Dec 2011 07:56:42 GMT Xfce for Gnome 2 Refugees http://www.kirsle.net/blog/kirsle/xfce-for-gnome-2-refugees Ever since I jumped ship from Gnome to Xfce a few years ago when <a href="/blog/kirsle/category/Gnome%203">Gnome 3/Shell</a> was first announced, I've configured my Xfce desktops to strongly resemble the standard Gnome 2 panel layout. <a href="/creativity/articles/xfce-gnome2.png">[image]</a> Click the screenshot for the full size version. Along the top panel I have my Applications and Places menus, app launchers for my commonly used programs, my CPU usage graph, notification area and clock. On the bottom panel are my task bar and workspace switcher. These are all standard Xfce panel applets. The details for anyone who's interested (the only panel applet options shown are the ones that differ from the default options): <ul> <li>Top Panel: Orientation: Horizontal Size (pixels): 24 Length (%): 100 <ul> <li>Applications Menu Button title: Applications Icon: a Fedora icon in /usr/share/pixmaps...</li> <li>Places Menu Show: Label Only Label: Places</li> <li>Separator</li> <li>Many Launcher applets for my commonly used programs</li> <li>Separator Style: Transparent Expand: checked</li> <li>Brightness plugin</li> <li>Screenshot</li> <li>CPU Graph: Background: black Width: 48 Show frame: checked Show border: unchecked</li> <li>Separator</li> <li>Notification Area</li> <li>Separator</li> <li>DateTime: Layout Format: Date Only Date Format: Custom: %a %b %e, %l:%M %p The DateTime applet has a drop-down calendar, unlike the normal Clock applet.</li> </ul> </li> <li>Bottom Panel: Orientation: Horizontal Size (pixels): 24 Length (%): 100 <ul> <li>Window Buttons</li> <li>Workspace Switcher</li> </ul> </li> </ul> So, any Gnome 2 refugees who can't stand Gnome 3... Xfce 4.8 is a very good option and you can configure it to look and feel just like Gnome 2. [image] Mon, 14 Nov 2011 03:42:39 GMT Sequence Breaking http://www.kirsle.net/blog/kirsle/sequence-breaking I spent most of the day today toying around with Pokemon FireRed Version - trying to sequence break it, mostly. [image] Originally, I wanted to see what would happen if you got to Fuchsia City without having taken one of the fossils from Mt. Moon... because in the Fuchsia City Zoo, there will be either an Omanyte or a Kabuto there -- the opposite fossil from the one you chose early in the game. So I wanted to see what the game would do... But then I realized that, Fuchsia City is the perfect city to start the game in because, while there's a steep difficulty curve to get your bearings, you can actually continue the game from there and get back on track. This can't be said of all the other cities (especially Cinnabar Island). I've divided my whole quest up into four parts, complete with screenshots. <a href="/firered">Read about my sequence breaking quest here.</a> Sun, 30 Oct 2011 04:30:14 GMT