As of 2016-02-26, there will be no more posts for this blog. s/blog/pba/
Showing posts with label awk. Show all posts

awkaster is a pseudo 3D action shooter game, its not really real-time, because it steps upon each keystroke, which is basically is the clock of the game.

https://lh3.googleusercontent.com/-dPM3Ltm52DM/VqlSYA-Vy3I/AAAAAAAAJDo/_-MlbXSLYYI/s800-Ic42/awk-raycaster.gif

Click to watch full map played

You have 100HP and a gun, your goal is to reach the elevator, which arrives in 1,000 moves. Once you get there and take it, you win the game. You can move with WASD with J/L for turning and Space to fire your weapon to kill red ball enemies. Limitless bullets, but one at a time.

There is four color modes, plain ASCII and/or with colors.

awkaster was created by Fedor Kalugin, written in GNU Awk with terminal size 128x49+ under the MIT License, currently git-016a1d4 (2016-01-17).

I wanted to know how I could monitor file system changes, especially activities on my home directory, and this was about this thread. I was thinking the issue could be solved by generating a snapshot of files using find, then watching changes and making changes to the snapshot file. Using grep to do the search.

But, thats simply stupid. Just using find would do that OP wants since that program OP uses only search for file names and folder names. For the first run of find it might be slower, 31000 more files took about six seconds. Well its not really slow. The consecutive runs only take about 0.1 seconds even after you add or delete files.

Anyway, its still fun to know how to monitor files. I installed inotify-tools package for inotifywait program.

http://farm6.static.flickr.com/5087/5205625460_60c806f25a.jpg

Here is the script I use:

inotifywait -m -r --format $'%T %e %w%f' --timefmt '%H:%M:%S' --exclude ~/'(\.mozilla|Documents/KeepNote)' -e modify -e move -e create -e delete ~ 2>&1 | awk '/^[0-9]/ {
sub(/'"${HOME//\//\\/}"'/, "~", $0)
split($0, a, " ")
len=length(a[1])+length(a[2])+1
printf "%-20s %s\n", substr($0, 0, len), substr($0, len+2)
// flush stdout
system("")
next
}
{print ; system("")}
' | tee -a /tmp/home_monitor

-m and -r are for recursively monitoring on files. I set up the output format and timestamp format. I exclude two things from being listed, one is ~/.mozilla and another is KeepNotes files. You can only have one --exclude supplied, if you have more than one, then only the last one would be effective. You have to group them up. -e specify events you want to monitor.

I use awk to do format adjustment, column alignment. Also replacing the literal of your home directory, /home/username, with just ~. Then I pipe the output to tee, so I can see on screen and write output to file at the same time. This way, Conky can ${tail /tmp/home_monitor 10} the file.

I was planning to use named pipe:

% MPIPE=/tmp/home_monitor
$ mkfifo $MPIPE
$ inotifywait ... | awk ... >$MPIPE
$ tail -f $MPIPE

It will save some disk space, but it doesnt work with Conky.

If you want to clean up /tmp/home_monitor when it gets too big, just do echo '' > /tmp/home_monitor. An important note for you, when you tail a file in Conky, make sure it exists. If you remove the file, Conky exits. I was hoping there was a Conky variable would run program in a thread and do similar task as $tail does, only the input is the standard output of that thread not a file.

By the way, I had never thought even in my own home directory would have many activities.

I recently found out I could use qlop -gH package or qlop -tH package to get merge time:

http://farm2.static.flickr.com/1010/5190755414_3fef86bebf.jpg

But it doesnt have an option to list packages merged in a session. So I wrote one to parse /var/log/emerge.log on its own, last-merge-time.sh:

http://farm2.static.flickr.com/1039/5190755456_e4530fd6a5.jpg

I tried to mimic the result format.

The merge time calculation is different than qlop, you might see difference in a few seconds. The script uses sed to filter unwanted merge log and keeps the last merge, then uses awk to format the output. You probably noticed that interrupted in the screenshot1 above, its a result of user interruption (pressing Ctrl+C) while merging. The timestamp is the start time, not the end time of merging as shown by qlop, I am just too lazy to change my code.

Of course, there is also the last sync time.

[1]The screenshot shows the result by feeding the script with hand-modified raw log.

chronic is a Perl script from moreutils collection, runs a command quietly. It eats up the output of the command, but if the command exits with error, which is exit status does not equal to zero, then chronic would show you the output.

From its manpage, it provides a clear example how it could be useful with cron:

0 1 * * * chronic backup # instead of backup >/dev/null 2>&1

Note

I use vixin cron, I dont need to redirect stderr to stdout, just chronic backup >/dev/null would do in the old way.

The old way, using redirection is fine, would not give you message sent to stdout since they are redirected to /dev/null, thought you would see get stderr message from log or email if you have sent up.

chronic would get you both.

I made a simple Bash script, chronic.sh: