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# install wget, if missing
yum install wget

# find a mirror http://isoredirect.centos.org/centos/8/isos/x86_64/CentOS-8-x86_64-1905-dvd1.iso
# replace url with your mirror
wget http://centos.mirror.constant.com/8.0.1905/isos/x86_64/CentOS-8-x86_64-1905-dvd1.iso

# with usb unplugged check for your current devices
ls /dev/s*

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; SPF (Sender Policy Framework) is an email authentication protocol 
; that allows the owner of a domain to specify which mail servers they use to send mail from that domain.
;
; explanation
; https://postmarkapp.com/blog/explaining-spf 
;
; mailchimp                     include:servers.mcsv.net        https://mailchimp.com/help/set-up-custom-domain-authentication-dkim-and-spf/
; gmail                         include:_spf.google.com         https://support.google.com/a/answer/33786?hl=en
; on-premises mail              ip4:x.x.x.x/24             

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# add Virtual Box repo
sudo dnf config-manager --add-repo=https://download.virtualbox.org/virtualbox/rpm/el/virtualbox.repo
sudo rpm --import https://www.virtualbox.org/download/oracle_vbox.asc

# install VirtualBox 6
sudo dnf install VirtualBox-6.0

# install depenency to avoid issue running containers
sudo dnf install kernel-headers.x86_64 gcc perl make 
sudo dnf install kernel-devel kernel-devel-4.18.0-80.el8.x86_64 elfutils-libelf-devel.x86_64

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Formula
METHOD_NAME = [CONTEXT] + VERB + [HOW]

METHOD_NAME
Must use camelCase (reference Zend Certificated Engineer study manual, Composer, and PSR standards).
Must not start with “__” unless it’s a predefined magic method.
Must start with an alphabetical character. 

CONTEXT
Should be a noun.

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<?php
$uid = 'username';
$password = 'password';

echo 'Try login as uid "' . $uid . '" using password [redacted]<br><br>' . PHP_EOL;

// connect
$ldapconn = ldap_connect('ldap://ldap.example.com');
if (!$ldapconn) {
    echo 'Could not connect to authentication server.' . PHP_EOL;

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SELECT 
    `mdl_course`.`id` AS `course_id`, 
    `mdl_course`.`shortname` AS `course_name`, 
    `mdl_user`.`email` AS `email_address`, 
    `mdl_user`.`firstname` AS `first_name`, 
    CASE 
WHEN `mdl_role_assignments`.`roleid` = 1 THEN 'Manager' 
WHEN `mdl_role_assignments`.`roleid` = 2 THEN 'Course creator' 
WHEN `mdl_role_assignments`.`roleid` = 3 THEN 'Teacher' 
WHEN `mdl_role_assignments`.`roleid` = 4 THEN 'Non-editing teacher' 

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# Generate SSH Key
ssh-keygen -o -f ~/.ssh/www.example.com

# Add SSH key to your SSH config
vim ~/.ssh/config 
Host www.example.com
    User git
    HostName www.example.com
    IdentityFile ~/.ssh/www.example.com

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<?php
// save the image locally
$image = file_get_contents('http://ipcamera.example.com/oneshotimage');
$datetime = new DateTime();
$filename = $datetime->format('Y-m-d H:i:s') . '.jpg';
file_put_contents($filename, $image);

/*
 *
 * Afterwards, compile video, e.g.

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A conflict exist when you try to print screen inside a VirtualBox container, as the screenshot
will be captured by the VirtualBox host. Ideally, to avoid this you'll want to set the host's keyboard 
shortcuts, the VirtualBox's host machine prefrences, and the VirtualBox keyboard shortcuts to a combination
that does not conflict and works for your workflow.

Personally, on the VirtualBox host, I am not interested in taking screenshots (as nearly exclusively inside
containers). Therefore, I will remove all screenshot shortcuts from the VirtualBox host. On CentOs 7 and
Ubuntu 18 this is under located Keyboard > Screenshot. 

Next, under VirtualBox Preferences > Input > Virtual Machine I will set the Host Key Combination to a key

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# initate a package
composer init

# push package to repository
git add .
git commit -m 'Init repo'
git push

# create a release in repository
https://github.com/hxtree/PXP/tree/v0.1.1-beta