These are short observations on Linux, it's use, programming, operation, and configuration. Mostly, they are derived from my own experiences installing, configuring and using Linux systems, from embedded systems to desktops to servers.
I have read that no program can ignore SIGKILL and SIGSTOP. But, a task is in UNINTERRUPTIBLE state when it sleeps blocking all signals. Could someone help me understand the scenario? Isn't it blocking all signals (including SIGKILL and SIGSTOP)?
Someone posted this question to one of the Linux newsgroups I follow:
Can someone give me a simple explanation of the difference between a soft link and a hard link? The documentation I've read mention these links but make no strong explanations of their meaning and how/when to use them. Thanks!
With my desktop machine's last system upgrade, I changed how I managed my /tmp directory. Before the upgrade, my configuration mounted a tmpfs on /tmp at startup, but now, it mounts a separate ext2 partition for /tmp. Linux implements the tmpfs filesystemtype in swap, making the contents of the directory really temporary; files and directories in such a filesystem vanish on reboot. But, now with the ext2 filesystem, /tmp files and directories stick around.
A while back, I needed a yearly calendar for my X desktop. Since, at the time, I ran a desktop that did not include an integrated Calendaring facility, I couldn't just click on something. So, I built a GUI perpetual calendar, in a shell script.
The script (which I called Xcal.sh) looked like
#!/bin/bash
WHEN=`date +%Y`
RC=0
while [ $RC -ne 103 ]
do
PREV=`expr $WHEN - 1`
NEXT=`expr $WHEN + 1`
cal $WHEN | \
xmessage -buttons $PREV,$NEXT,Quit -file - -title "In the Year $WHEN"
RC=$?
case $RC in
