## Fixing group permissions in sshfs via OSXfuse

One could mount SSHFS partitions on a Mac OS X system via OSXfuse and MacFusion to access remote files securely as if the files were stored locally. However, group permission seems to not be preserved (get a permission denied message). This post shows how one could fix it by using the -o defer_permissions options.

## How programs run on Linux

This is an excellent article describing how statically linked programs run on Linux.

## Screen brightness after suspend in Ubuntu

Many laptops have their screens dimmed after returning from “suspend” and cannot get back to their original brightness. The bug hasn’t been fixed for 3 years. A fix is provided in the bug report by putting something like the following in /etc/rc.local:

<pre class="src src-sh"><span style="color: #eedd82;">brt</span>=<span style="color: #fa8072;">cat /sys/devices/virtual/backlight/acpi_video0/brightness</span>




## Record streaming radio with streamripper

Yes, many radio shows are available as podcasts. However, some are not. If a radio show is also broadcasted via a live stream online, then we could record it with streamripper. I did so as follow:

<pre class="src src-sh">sudo apt-get install streamripper <span style="color: #ff4500;">## </span><span style="color: #ff4500;">install</span>


## record for 60 seconds streamripper http://kpcclive1.publicradio.org:80/ -s -l 60 -a “Prarie – %d”

To have the show be recorded automatically, first create record.sh:

#! /bin/bash

## set in crontab:
## 59 17 * * 6 /path/to/record.sh
cd /path/to/save/; streamripper http://kpcclive1.publicradio.org:80/ -s -l 3720 -a "Prarie - %d" &> /dev/null


Then add the following cron entry via crontab -e:

59 17 * * 6 /path/to/record.sh


## Test ram with Memtest86+ and ignore bad parts with badram in grub

Recently, my computer kept freezing whenever I started conkeror (with 100+ buffers loading from a previous session). Folks over at #conkeror on freenode suggested that the problem might be due to faulty ram. They suggested testing my ram with Memtest86+. It is installed by default on Ubuntu.

If you have multiple sticks of ram, test one stick at a time. It’s best to test one stick per night as the test can take hours. To test the ram, restart your computer and go to the grub menu (hold shift if your grub menu doesn’t display automatically). Then, select the “Memtest86+” boot option. Press “c”, “4”, and “3” to display the error locations according to the BadRAM syntax (converting the default faulty memory addresses is not obvious to me and others). If you don’t do this, you will end up wasting time fixing your boot options (details later).

If you know which ram sticks are bad, replace them if they are under warranty. If they are not under warranty and you can’t afford new ram, you can make use of BadRAM, incorporated by default in grub2, per these documentations. That is, edit /etc/default/grub and specify the faulty ram addresses with the GRUB_BADRAM option.

More information on running Linux with broken memory can be found here.

When I tried this out, I did not use the proper memory address syntax so my computer failed to boot. What made things even worse was that my hard drive was encrypted. Luckily, I can still access grub, and after many trials and tribulations, I fixed the problem by booting the computer with an Ubuntu live disk (usb), mounting the first, unencrypted partition (/dev/sda1) of the hard drive that stored /boot, and removing the badram option in /boot/grub/grub.cfg (replace “boot” with the mount path). Before figuring out the solution, I was trying to mount /dev/sda5, the encrypted partition, according to this and this as I thought that was where /boot resided. I also thought I had to generate a new initrd image. Luckily I didn’t have to (and didn’t succeed in trying) as that would have further complicate my boot options as I have experienced in the past.

After removing the bad ram, conkeror still crashed for me. Either something is wrong with other pieces of my hardware or something is going on with the xulrunner sucking up my system resources. I was able to stop the crashes by placing this in my conkeror rc file.