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+Miscellanous Notes
+==================
+    
+A collection of short notes on things I wish to remember. Many topics are heavily outdated.
+
+Backing up and Restoring Docker Volumes
+---------------------------------------
+
+    July 3, 2017
+
+One of my first questions, when starting my docker experience was 
+how to backup and restore docker volumes.
+
+### On the source host
+
+First of all identify your volumes:
+
+    $ docker ps
+    $ docker inspect my_container_name | grep -C 1 -i Source
+
+Now you can backup the directory to a tar on your host machine:
+
+    $ docker run –rm –volumes-from my_container_name -v $(pwd):/backup ubuntu tar cvf /backup/backup_db.tar /var/lib/mysql
+
+### On the target host
+
+In order to securely copy and restore the volume on the target host one can run:
+
+    $ scp source_host:~/backup_db.tar .
+    $ docker run –rm –volumes-frommy_container_name -v $(pwd):/backup ubuntu bash -c “cd /var/lib/mysql && tar xvf /backup/backup_db.tar –strip 1″
+
+A Growing Collection of Linux Command Line One-Liners
+------------------------------------------------------
+
+Please believe me... this collection was really supposed to grow over time...
+
+inside a direcotry show disk usage of all hidden files and directories and sort by size:
+
+    $ du $(ls .* -d | tail -n +3) -hs |sort -h
+
+inside a direcotry show disk usage of all files and directories (also hidden) and sort by size.
+Exclude ./DATA file.
+
+    $ du . -a -d 1 -h –exclude=’./DATA’ | sort -h
+
+Tar all files in current directory, excluding ./DATA and ./.cache
+
+    $ tar –exclude=’./.cache’ –exclude=’./DATA’ -cvf home_miguel_20180216.tar .
+
+Find files in ./ARCHIVE NOT belonging to a specific user: miguel
+
+    $ find ARCHIVE/ \! -user miguel
+
+set folder/ permissions to Read/Browse only for owner recursively
+
+    $ sudo chmod -R u=r,g=,o= folder/
+    $ chmod -R u=rX,g=,o= folder/
+
+find all mails from Boban when in the maildir full of mailboxes and print only short headers without bodies:
+
+    $ grepmail -H -B -Y ‘(^TO:|^From:)’ Boban *
+
+not really a one-lier but will print 256 colors in a bash:
+
+    for i in {0..255} ; do
+        printf "\x1b[48;5;%sm%3d\e[0m " "$i" "$i"
+        if (( i == 15 )) || (( i > 15 )) && (( (i-15) % 6 == 0 )); then
+            printf "\n";
+        fi
+    done
+
+Some Tools of Choice
+--------------------
+
+### Systems
+
+* joomla
+* redaxo
+* typo3
+* wordpress
+* mediawiki
+
+* oscommerce
+* opencart
+
+* owncloud
+* alfresco
+* mantis
+
+* piwik / matomo
+* loganalyzer
+* goaccess
+* nagios / icinga
+
+### Servers
+
+* apache
+* nginx
+
+* mariadb / mysql
+* postfix
+* postgis
+
+* geoserver
+
+<!--
+## Tools / Servers
+    openlayers
+    git / gitweb / stagit / gitolite
+    xmpp
+    mumble
+    docker / registry
+    kvm
+    kubernetes
+    postfix/dovecot / rouncube/postfixadmin
+    symfony
+    bootstrap
+    webGL
+    websockets
+    ajax
+    node/angular
+    jmeter
+    ceph
+-->
+
+Compilation Notes
+-----------------
+
+### build your own webkit
+
+    March 14, 2018
+
+Let’s compile a release with debug info and install to /usr/local
+
+~~~~~~ {.bash}
+wget https://webkitgtk.org/releases/webkitgtk-2.20.0.tar.xz
+tar -xvf webkitgtk-2.20.0.tar.xz
+cd webkitgtk-2.20.0
+# install all the libs that will be reported missing in the next step.
+# I could not find the woff2 stuff in debian so skipped it... 
+cmake -DPORT=GTK -DCMAKE_BUILD_TYPE=RelWithDebInfo -DUSE_WOFF2=NO -GNinja
+# this takes about 30minutes on my i7-4790K .. zzzzz..zzz
+ninja
+sudo ninja install
+~~~~~~~~~~~
+
+    pkg-config
+
+    pkg-config uses our new build now:
+
+    [1] https://trac.webkit.org/wiki/BuildingGtk
+    [2] https://webkitgtk.org/
+
+### Build and Install GCC
+
+    April 27, 2015
+
+#### Preparations
+Read the prequisites at 
+[https://gcc.gnu.org/install/prerequisites.html](https://gcc.gnu.org/install/prerequisites.html) 
+and get (most recent versions at time of  this writing) the following:
+
+* gcc (5.2.0)
+* binutils (2.25.1)
+
+#### Configure and Build
+
+* unpack binutils-x.y.z
+* create a new directory binutils-x.y.z-build and inside it run the following commands:
+
+~~~~~~ {.bash}
+    $ ../binutils-x.y.z/configure --disable-nls --with-sysroot --enable-targets=all
+    $ make -j4
+    $ make install
+~~~~~~~~~~~~
+
+* unpack gcc-x.y.z and run the contrib/download_prerequisites script inside.
+* create a new directory: gcc-x.y.z-build and inside it run:
+    
+~~~~~~ {.bash}
+    $ ../gcc-x.y.z/configure --disable-nls --enable-languages=c,c++ --enable-threads
+    $ make -j4
+    $ make install
+~~~~~~~~~~~~
+
+#### Reference
+    [1] binutils and gcc README files.
+    [2] https://gcc.gnu.org/install/
+    [3] http://wiki.osdev.org/Building_GCC
+    [4] http://stackoverflow.com/questions/1726042/recipe-for-compiling-binutils-gcc-together
+
+monad transformers in action
+----------------------------
+    January 1,2018 
+    
+    *Main Control.Monad.Writer Control.Monad.State> runState (runWriterT  (get >>= \a -> tell ["foo"] >> put (a*a) >> tell ["bar"] >> tell [show a])) 5
+
+emscripten
+----------
+    October 1,2017
+
+    sdl2 port
+    https://github.com/juj/emsdk
+    android-ndk-r15c
+
+    * accomplish build sys with: sdl2+input+audio+opengl+SDL_net+SDL_thread @ linux, win, osx, ios, android, win-phone, steam, rasp
+
+LUKS container over sshfs
+-------------------------
+    July 5, 2017
+
+* enable user\_allow\_other in /etc/fuse.conf
+* sshfs -o allow\_root user@server:/BACKUPS/ ~/mnt/
+* dd if=/dev/urandom of=~/mnt/megaloman bs=1M count=512
+* sudo cryptsetup -y luksFormat ~/mnt/megaloman
+* sudo cryptsetup luksOpen ~/mnt/megaloman vol1
+* sudo mkfs.ext4 /dev/mapper/vol1
+* sudo mount /dev/mapper/vol1 /mnt
+* df -h | grep vol1
+* sudo umount /mnt
+* sudo cryptsetup luksClose vol1
+* fusermount -u ~/mnt
+
+NOTE: backup your data example use : rsync -a –info=progress2 source dist
+
+some areas of interest
+----------------------
+    December 20, 2014
+
+Some General Topics I am reasearching right now (or plan to do it). Or used to reasearch...
+
+* Neuronal Networks
+* Deep Learning
+* Random Forrests (and other techniques based on Decision Trees)
+* Simmulated Annealing
+* (Linear) Integer Programming
+
+
+Inter Process Communication
+---------------------------
+    March 14, 2018
+
+We can attach nicely to same memory segment from 2 different processes:
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ {.c .numberLines}
+// ipc via shared mem
+// attach to shared memory;
+key_t my_ftok = ftok("~/surf-webext-dom-shared-mem",'a');
+ 
+int mem_seg=shmget(my_ftok,1024*1024,IPC_CREAT|0660);
+if(mem_seg==-1)
+{
+g_print("shmget failed: %s\n",strerror(errno));
+}
+ 
+shared_buf=shmat(mem_seg,NULL,0);
+if(shared_buf==(void*)-1)
+{
+g_print("shmat failed: %s\n",strerror(errno));
+}
+g_print("attached to shared memory.\n");
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+SSL Certificate CSR
+-------------------
+    
+    February 20, 2015
+
+    for apache ssl mod
+
+    first check your old csr if you like:
+    $ openssl req -text -noout -verify -in CSR.csr
+    
+    1. generate key
+    $ openssl genrsa -des3 -out www.yourdomain-example.com.key 2048
+    
+    2. create CSR
+    $ openssl req -new -key www.yourdomain-example.com.key -out www.yourdomain-example.com.csr
+    
+    refs:
+    [1] https://search.thawte.com/support/ssl-digital-certificates/index?page=content&id=AR1108&actp=LIST
+
+Competitive Coding
+------------------
+    March 17, 2015
+
+A small selection of websites, which I visit from time to time, addressing competitive coding.
+
+* topcoder.com
+* codeforces.com
+* codility.com
+* codersclan.ne
+* projecteuler.net
+* www.codingame.com (need to check this)
+* www.codechef.com (need to check this)
+* http://psyho.gg/overview-of-programming-contests/ (and read here)
+* https://www.hackerrank.com/
+* http://code.google.com/codejam
+* https://www.kaggle.com/ – predicitve modelling
+* odesk.com / elance
+
+Comp Science Literature
+-----------------------
+    March 17, 2015
+This is a list of some books, focusing on topics around computer science, which I recently read or am currently reading or want to read :P
+
+* Meyers, Effective C++ (Addison-Wesley) C++98 only?
+* Meyers, More Effective C++ (Addison-Wesley) C++98 only?
+* Meyers, Effective STL. C++98 only?
+* Sutter, Exceptional C++
+* Sutter, More Exceptional C++
+* Karlson, Beyond the C++ Standard Library: An Introduction to Boost 1st Edition
+* Maybe Something on Multiprocessing (?)
+* Donald Knuth. The Art Of Computer Programming
+* Algorithms 3rd Edition (by Cormen, Leiserson, Rivest, Stein)
+* Jonathan Bartlett. Programming from the Ground Up
+* C++ in a Nutshell (O’REILLEY, by Lischner)
+* C++ Primer (5th Edition) by Lippman, Lajoie, Moo
+* The C++ Programming Language 4th Edition
+* Anthony Williams, C++ Concurrency in Action: Practical Multihreading
+* Dive into Python (2 and 3) by Mark Pilgrim
+* Learn You a Haskell for Great Good by Marian Lipovaca
+* Real World Haskell
+* Version Control with Git (O’REILLEY, by Loeliger & McCullough) (next: 9(10) ?)
+* The Linux Command Line, by William Shotts (http://linuxcommand.org/tlcl.php)
+* Debian, The Administrators Handbook (by Hertzog and Mas)
+* Absolute FreeBSD by Michael W. Lucas
+* Modern Operating Systems, Third Edition (by Andrew S. Tannebaum)
+* Linux Device Drivers (O’REILLEY, by Corbert, Rubini, Kroah-Hartman)
+* Linux Kernel in a Nutshell (O’REILLEY,  Greg Kroah-Hartman)
+
+* Concrete Math (2nd)
+* UPENN cis194
+
+* STOC '83 Proceedings of the fifteenth annual ACM symposium on Theory of computing / Primitives for the manipulation of general subdivisions and the computation of Voronoi diagrams
+
+* http://haskellbook.com/
+* Wadler paper "Monads for Functional Programming"
+* simon marlow - book (parallel)
+* data 6 - course (Github)
+* sedgewick & waynes algorithms
+* books from appendix, from programming from ground up?
+
+VNC
+---
+    April 2, 2015
+
+### Server:
+    $ apt-get install tightvncserver
+    $ xtightvncserver -geometry 1900×1100
+    $ netstat -tap | grep vnc # remember port (e.g.5901)
+
+### Client:
+    $ ssh -L 5901:localhost:5901 you@remote # tunnel
+    $ xtightvncviewer localhost::5901 # in new terminal
+
+### Kill Server:
+    $ vncserver -kill :1 # (or :2 etc..)
+
+Owncloud Notes
+--------------
+
+### Mounting Ownclouds DavFS
+
+    April 15, 2015
+
+    $ apt-get install davfs2
+
+    * since owncloud seems to have problems with locks, edit /etc/davfs2/davfs2.conf and set use_locks to 0 in order to allow creating files (as well as probably writing)
+
+    $ mount -t davfs https://secure.sf.com/owncloud/remote.php/webdav /mnt/
+
+### rescan/rebuild ownlocud files database
+
+    June 22, 2016
+
+    inside ownlcoud  directory run:
+    sudo -u www-owncloud php console.php files:scan –all
+
+
+LXC
+---
+    April 28, 2015
+
+    maybe worth a try:
+
+    apt-get install lxc; lxc create ctname -t download — -d debian -r jessie
+    -a amd64; lxc-start -d -n ctname, lxc-attach ctname
+
+    similar tools: chroot/ debootsrap
+
+Add vim Lang
+------------
+    May 14, 2015 
+
+    $ sudo apt-get install myspell-pl
+    $ cd /ush/share/hunspell
+    $ vim
+    :mkspell pl pl_PL
+
+What every programmer should know about
+---------------------------------------
+    November 7, 2015
+
+    Undefined behaviour: http://blog.llvm.org/2011/05/what-every-c-programmer-should-know.html
+    Memory: http://lwn.net/Articles/250967/
+    Floating point arithmetic: https://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html
+
+IDE Comparison
+--------------
+
+    December 7, 2015
+
+While I love working with vim (ctags, taglist, etc..) and the command line, it might be worth to have a look at the following IDE’s for Java and/or C++:
+
+* IntelliJ IDEA
+* Eclipse
+* Eclipse CDT
+* Codeblocks
+* Netbeans
+* Codelite
+* KDevelop
+
+Setup Postfix
+-------------
+
+We want to handle different domains on a single postfix server and have virtual users along real unix users. For the virtual users we use uid/gid 5000.
+
+Relevant config files are:
+
+    /etc/postfix/master.cf
+    /etc/postfix/main.cf
+    /etc/postfix/smtpd_sender_login_maps (tells which emails belong to which login)
+    /etc/postfix/vmailbox (sepcifies our VIRTUAL mailboxes and the names of the spoolfiles)
+    /etc/postfix/virtual (aliases for our local unix users)
+    /etc/dovecot/users (specifies the logins, passwords, home directories,..)
+    /etc/dovecot/conf.d/10-mail (set inbox and mailbox dirs)
+
+Be careful about the permissions of the different folders, so uid/gid 5000, postfix and dovecot can access as relevant.
+
+A very nice tutorial on setting up postfixadmin can be found here: 
+
+    https://lelutin.ca/posts/installing_postfix_-_clamav_-_spamassassin_-_dovecot_-_postfixadmin_on_debian_squeeze/
+
+Windows Specific Notes
+----------------------
+
+### disable hiberfile.sys
+
+    September 7, 2017
+
+    run cmd.exe as administrator:
+    powercfg.exe -h off
+
+### GTA4 on NVIDIA-GTX 980
+
+    April 17, 2016
+
+    Add following flags : -nomemrestrict -norestriction
+    Otherwise video memory is not identified correctly.
+
+### Civilization 4 BTS Autosaves
+
+    September 23, 2016
+
+    In the file: C:\Users\miguel\Documents\My Games\Beyond the Sword\CivilizationIV
+
+    Adjust:
+
+    ; The maximum number of autosaves kept in the directory before being deleted.
+    MaxAutoSaves = 100
+
+    ; Specify the number of turns between autoSaves. 0 means no autosave.
+    AutoSaveInterval = 1
+