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[terminal heroes] Display git branch in shell prompt (PS1)

Ktoso — Sat, 26 Feb 2011 22:29:01 +0000

I don’t think I’ve blogged about this but I’ve seen this sometime ago and now decided to add it to my .bashrc for good. It’s a simple trick to make an awesome PS1 shell prompt, displaying the branch you are currently on (if you’re in a git versioned directory). Not that I’m forgetting what branch I’m on, but I hope it’ll make me create more branches more often and never “just work on master” :-)

The code comes from http://arnorehn.de/cgi-bin/weblog_basic/index.php?p=34 so big kudos too him :-)

# in your ~/.bashrc for example
alias gitka='gitk –all' #unrelated to this post, but very useful :-)
function formattedGitBranch {
_branch="$(git branch 2>/dev/null | sed -e "/^\s/d" -e "s/^\*\s//")"
test -n "$_branch" && echo -e " @\e[0;32m $_branch"
}
#export PS1="\u@\h \W \[\e[m\]\$(formattedGitBranch) \[\e[1;32m\]\$ \[\e[m\]\[\e[0m\]"
export PS1="\u@\h \W\[\e[m\]\$(formattedGitBranch)\[\e[0m\] \$ "

Cheers and happy hacking!

PS: I’m waiting for my T-shirt and stickers (for training participants) to arrive from github. I’d love they make it in time for SFI but I’m not sure if it’s even possible hmmm…

G73 keyboard backlight scripts

Ktoso — Sat, 29 Jan 2011 19:09:42 +0000

I’ve upgraded my desktop and laptop last week. By “and” I mean that I’ve bought an desktop replacement class notebook – an Asus G73 series. Amongst many nice parts it has I’m very happy about the harddrives – Seagate Momentus XT, click the link to see an very interesting benchmark of it. Anyways, that’s not what this post should be about.

The G73 has an backlit keyboard, which may come in handy while late night coding without lights on as I like to code sometimes. (I’m using a X6 Sidewinder, even with this Notebook so it’s not like it’s keyboard matters to me most of the time ;-)) As usual with such “super cool addons” the funtion keys regulating the keyboard backlight seemed to only work on Windows – which I’m only using for gaming (but rarely) and testing if the software I happened to write runs ok on it. Anyways, turns out that the keyboard does really well integrate with linux, and you just need a few simple commands to use it, I’ve made them available on github :-)

https://github.com/ktoso/g73-keyboard-backlight-sh <- Go here to check it out :-)

Asus G73 Keyboard Backlight GNU/Linux Scripts

=============================================
To enable the `Fn + F3` and `Fn + F4` shortcuts to work under linux and really
manipulate the backlight brighntess on your *Asus G73* series notebook, follow theese simple steps:
1. Clone this repository to your home directory (or wherever you want to, I'll do this example for ~/ for simplicity)
cd
git clone git://github.com/ktoso/g73-keyboard-backlight-sh.git g73
2. Make sure all scripts are marked executable:
cd g73
chmod +x *.sh
3. Take a look at these scripts to make sure you trust them, why? Because they'll need root access,
without asking for the password. Now we'll add these scripts to allow `sudo`to run them without
asking for any password:
su -c 'visudo' # or 'sudo visudo' if you're a sudoer (on ubuntu etc)
There just add the following lines at the end of this file (or similar, with the script names etc).
Of course, replace `ktoso` and `/home/ktoso/` with your *username* and *your home directory*.
## allow running keyboard backlight scripts
ktoso ALL=(ALL) NOPASSWD:/home/ktoso/g73/*
4. Now all that's left is to setup the key bindings for the scripts. If you're on KDE4, just go to
*System Settings -> Shortcuts and Gestures -> Custom Shortcuts* and *edit -> import…* the file **~/g73/g73_keyboard.khotkeys**
which contains ready keybindings for these scripts.
Now you may use `Fn + F3` to make the keyboard backlight shine **less**, and the `Fn + F4` combination to make it shine **more**.

Terminal Heroes 8: Memory usage scripts

Ktoso — Wed, 24 Feb 2010 10:54:21 +0000

I have a low-memory VPS running online and thus always have to worry about what uses how much memory… Of course top and my favorite htop are very good tools to check this, but sometimes I just want to get a super simple report if I’m overusing memory or not yet. The bellow scripts (most of them was found online or hacked up from multiple scripts to fit my needs) print simple yet very readable memory usage information.

memused

#!/bin/bash

#if [ $1 = '']; then
# ps auxf | awk '{sum=sum+$6}; END {print sum/1024}';
#else
# ps auxf | grep $1 | awk '{sum=sum+$6}; END {print sum/1024}';
#fi
bean=`cat /proc/user_beancounters` guar=`echo "$bean" | grep vmguar | awk '{ print $4;}'` burst=`echo "$bean" | grep privvm | awk '{ print $5;}'` priv=`echo "$bean" | grep privvm | awk '{ print $2;}'`
let total=guar/256 let used=priv/256 let burst=burst/256
echo "VPS memory usage:"
echo "Used: $used MB"
echo "Total: $total MB"
echo "Burstable to: $burst MB"

Sample output:
VPS memory usage: Used: 296 MB Total: 256 MB Burstable to: 512 MB

memfree

#!/bin/bash

#
# Revised 02-Feb-2007: include kernel memory (kmemsize) in 'used' calculation
# and show percentages in output.
#
BEAN=`cat /proc/user_beancounters`
GUAR=`echo "$BEAN" | grep vmguar | awk '{ print $4;}'`
PRIV=`echo "$BEAN" | grep privvm | awk '{ print $2;}'`
KMEM=`echo "$BEAN" | grep kmem | awk '{ print $3;}'`
let TOTL=$GUAR/256
let KMMB=$KMEM/1048576
let PVMB=$PRIV/256
let USED=$KMMB+$PVMB
let FREE=$TOTL-$USED
if [ "$FREE" -gt "0" ]; then
let UPER=$USED*100/$TOTL
let FPER=100-$UPER
else
let UPER="100"
let FPER="0"
fi
echo "VPS Memory:"
echo " Total: $TOTL mb Used: $USED mb (${UPER}%) Free: $FREE mb (${FPER}%)"

Sample output:
VPS Memory: Total: 256 mb Used: 302 mb (100%) Free: -46 mb (0%)

memheld

#!/bin/bash

grep oomguarpages /proc/user_beancounters | awk '{s=$2;t=$3;u=$4; {print "VPS Memory Usage\nCurrent Held: " s/256 "MB\nMax Held: " t/256 "MB\nBarrier: "u/256"MB" }}'

Sample output:
VPS Memory Usage Current Held: 160.832MB Max Held: 294.605MB Barrier: 256MB

memps

#!/bin/bash

echo "ps axo pmem,pcpu,comm | sort"
ps axo pmem,pcpu,comm | sort

Sample output:
ps axo pmem,pcpu,comm | sort 0.0 0.0 script 0.0 0.0 script 0.1 0.0 init #... 2.2 0.0 httpd 4.0 0.0 mysqld 7.3 0.0 httpd 8.0 0.0 httpd %MEM %CPU COMMAND

memprivmpages

#!/bin/bash

beans=`cat /proc/user_beancounters | grep priv`
max=`echo $beans | awk '{ print $4;}'`
use=`echo $beans | awk '{ print $2;}'`
let "per=$use*100/$max"
let "mb=$use/256"
let "mmb=$max/256"
echo "privvmpages usage: $mb MB ($per% of $mmb)"

Sample output:
privvmpages usage: 296 MB (57% of 512)
For those wondering, yes I do have memory usage above “100%” in the output of some of these scripts, and it’s partially true. A VPS does usually have some guaranteed memory, and some “burstable” – so you can use more than just the guaranteed memory for some period of time. On the mashine I ran this I have 256 guaranteed and a “total” of 512MB – including the burstable memory.

If you like any of these, feel free to use them. I use them by creating a scripts directory and adding it to the PATH, so I can simply invoke them from anywhere.

PS: For more detailed memory usage information (as graphs etc), I’m using Munin and really recommend it. The graphs it draws are really nice, and it doesn’t inflict heavy load on the server, and it can monitor remote hosts if needed!

Kill only Tomcat

Ktoso — Sun, 21 Feb 2010 22:14:47 +0000

There is sometimes the need to kill some JVM, I usually use “killall java” and that works fine as long as that’s in fact what I want – kill ALL. But let’s say i just want to kill Tomcat and not my IDE? The below method works quite well in such an situation:

[ktoso@homunculus ~]$ sudo netstat -lpn | grep 8080

tcp 0 0 :::8080 :::* LISTEN 18525/java
[ktoso@homunculus ~]$ kill 18525 # you might need to add -9 here (SIGKILL)

A quickly hacked up version of an simple shell script to kill this tomcat could look like (I still suck at awk…):

#!/bin/sh

kill -9 `netstat -lpn | grep 8080 | awk '{print $7}' | awk -F/ '{print $1}'`

The above obviously sux, as we’re using two awk commands after another… Ans also in the above examples, I’ve assumed that tomcat is listening on 8080, this may not always be the case, since with mod_proxy_ajp, there is no need fot it to listen on it’s default port and just the one to communicate by AJP. Let’s use it’s name to find it’s PID, we’ll use ps and grep and awk – life is simple with them. :-)
Here’s the final version of this command:

#!/bin/sh

kill -9 `ps aux | grep catalina | awk '{print $2}'`

AWK and multiple lines from shell command

Ktoso — Sun, 15 Nov 2009 15:11:16 +0000

Let’s say you want to read the ps output inside an AWK script, it’s not so simple since system returns an exit code and not the string you want – it’s being sent to stdout, here is a simple trick to read multiple lines from a shell command inside awk:
awk 'BEGIN{while ("ps aux" | getline){ print "test " $1 " test"}}' /dev/null | more

Terminal Heroes – 6 – Track X events

Ktoso — Sat, 19 Sep 2009 22:53:33 +0000

Another Command Line Fu oneliner I’ve sumbited today:

#show X window events in chosen window

$ xev -id `xwininfo | grep 'Window id' | awk '{print $4}'`
EnterNotify event, serial 13, synthetic NO, window 0×6400053,
root 0x13c, subw 0x640005b, time 42431610, (367,0), root:(369,63),
mode NotifyNormal, detail NotifyVirtual, same_screen YES,
focus NO, state 16
MotionNotify event, serial 13, synthetic NO, window 0×6400053,
root 0x13c, subw 0x640005b, time 42431610, (367,0), root:(369,63),
state 0×10, is_hint 0, same_screen YES
MotionNotify event, serial 13, synthetic NO, window 0×6400053,
root 0x13c, subw 0x640005b, time 42431618, (366,0), root:(368,63),
state 0×10, is_hint 0, same_screen YES

After executing this, click on a window you want to track X Window events in. You could “read” this command like this: “xev will track events in the window with the following -id, which we get by greping window information obtained by xwininfo” :-)

Ok, but why did I need such weird information? Well, I wanted to make a simple video showing vis, a vim plugin etc. But as it is always in vim, keypresses are essential – so I wanted to “show what i type” bigger :-) I’ll post it really soon btw… :-)

The command was posted on commandlinefu

Terminal Heroes – 4 – regexpias lair

Ktoso — Fri, 04 Sep 2009 00:24:11 +0000

Let’s drop a little humor in this time…

You, brave Terminal Hero, shall kill -9 the daemon that has hidden itself in one of those files! We don’t know in which file you can find it though! We’re running out of time! The kingdom of GNU will be rm -rf‘d if you won’t make it in time!!! Luckily as a level 99 human root, have all the tools to find and exterminate the dragon in no time! So let’s get greping.

[ktoso@lairs ~]$ ls

lair1 lair2 lair3 ……. lair1336
[ktoso@lairs ~]$ ls -l | wc -l
1337
[ktoso@lairs ~]$ find . -exec grep "Regexpia" '{}' \; -print
Regexpia is in this file
./lair1270
[ktoso@lairs ~]$ kill_dragon_inside lair1270

Ok, enough joking…This post is all about this one-liner:find . -exec grep "Onyxia" '{}' \; -print
It allows you to search all files (including sub directories) for the ones with the specified string inside them. It proved helpful to me as i had to get one *.php file from a photorec recovered bunch of files (some thousands of them…)…

Hope you had as much fun reading this as I had posting, and also that it might prove usefull to you. I found this on snipplr by the way, I really recommend this website!

PS: The title just sounds too awesome i think… If you didn’t get it, it’s about Onyxia’s Lair from World of Warcraft :-)

Terminal Heroes – 3 – ^^ typo fixing

Ktoso — Wed, 02 Sep 2009 03:04:45 +0000

A great bash feature I just discovered is the “^blabla^bla” command (is it a “command” by the way..?) If typing stuff quickly by hand, typing mistakes (typos) happen… And it’s not really fast to fix them by using UP ARROW and then fixing the command by “hand”… A better, quicker way to do this is the ^^ I mentioned, it works like this:[ktoso@homunculus /]# cd /home/ktozo -bash: cd: /home/ktozo: Nie ma takiego pliku ani katalogu [ktoso@homunculus /]# ^zo^so cd /home/ktoso [ktoso@homunculus ~]#So it’s basically a simple “replace and run” command… :-)