Linux: mount folder to different folders

Code:

mount -o bind /media/disk1/pictures /home/user1/pictures
mount -o bind /media/disk1/pictures /home/user2/pictures

for add a fstab entry to auto-mount at startup.

Code:

/media/disk1/pictures /home/add1cker/pictures none defaults,bind 0 0

OpenGL Tutorial

 Common libs for start

$sudo apt-get install freeglut3-dev

Matrix Class [3]

Error:
_dl_check_map_versions: Assertion `needed != ((void *)0)' failed!

Fixed using -lpthread parameter [2].


References:


[1] https://www.opengl.org/wiki/Programming_OpenGL_in_Linux:_GLX_and_Xlib

[2]  http://stackoverflow.com/questions/20007961/error-running-a-compiled-c-file-uses-opengl-error-inconsistency-detected
[3] http://www.songho.ca/opengl/index.html
     http://www.songho.ca/opengl/gl_matrix.html#example1
[4] Image Libraries
      https://www.opengl.org/wiki/Image_Libraries
[5] SFML
      http://www.sfml-dev.org/tutorials/2.3/start-linux.php

git commands

References:
[1] https://git-scm.com/book/en/v2/Git-Branching-Basic-Branching-and-Merging

Raspberry pi 3

1) user and passwords:

Distribution   | Username   | Password
---------------|------------|-------------
Debian Squeeze | pi         | raspberry
Arch           | root       | root
QtonPi         | root       | rootme
Raspbian       | pi         | raspberry
OpenElec       | root       | openelec
Pidora         | root       | raspberrypi
RISC OS        | n/a        | n/a
raspbmc        | pi         | raspberry

2) add users

$sudo adduser username

$usermod -aG sudo username

3) Ports

$lsof -nP -i | grep LISTEN
$netstat -tlpn | grep LISTEN
 

4) vncserver (reinstall, by default sometime doesn't works)

$sudo apt-get install tightvncserver 

5) Firewalls

iptables -I INPUT -p tcp --dport 5900 -j ACCEPT
iptables -I INPUT -p tcp --dport 5901 -j ACCEPT

Resources:

[1] https://www.digitalocean.com/community/tutorials/how-to-create-a-sudo-user-on-ubuntu-quickstart

[2] direct way https://www.shellhacks.com/how-to-grant-root-access-user-root-privileges-linux/

[3] vncserver https://quaintproject.wordpress.com/2013/03/24/establish-a-vnc-connection-to-your-raspberry-pi-from-a-linux-pc/

smoothing

References:

[1] smoothing python https://matthew-brett.github.io/teaching/smoothing_intro.html

Optimize code C/C++

If you are using linux: use getchar_unlocked() and putchar_unlocked() for taking fast single character I/O.
In Windows the equivalent is getchar() and puchar() repectively


Resources:
[1] fast input/output https://ideone.com/BrsDz4


Enteprise solutions:
[1] http://www.fastformat.org/

Computational Resources

Resources:
[1] Computational Biophysics Software http://www.ks.uiuc.edu/Research/vmd/vmd-1.9.1/

Programming online C++ and others

Online programming tools

Resources:
[1] C++, Python  https://repl.it/@melhorum


[2] Multi Language Support https://code.dcoder.tech/

[3] Account for C/C++, C#, Java  http://rextester.com
[4] http://www.onlinegdb.com/

Store on EEUU for Buy

Stores:
[1] https://www.shipito.com/pt/shipito-pricing

Python 2.7 pip

Resolving error on python 2.7 using pip: ImportError: No module named _internal

$wget https://pypi.python.org/packages/e7/a8/7556133689add8d1a54c0b14aeff0acb03c64707ce100ecd53934da1aa13/pip-8.1.2.tar.gz
$tar -xzvf pip-8.1.2.tar.gz
$cd pip-8.1.2
$sudo python setup.py install