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To get the name of the current function - type: my_function() { echo "This function is $FUNCNAME" # This will output "This function is my_function" } This instruction will return nothing if you type it outside the function: my_function echo "This function i...

The hostname assigned to the system during startup. ~> $ echo $HOSTNAME mybox.mydomain.com

Similar to $HOSTTYPE above, this also includes information about the OS as well as hardware ~> $ echo $MACHTYPE x86_64-redhat-linux-gnu

The search path for finding binaries for commands. Common examples include /usr/bin and /usr/local/bin. When a user or script attempts to run a command, the paths in $PATH are searched in order to find a matching file with execute permission. The directories in $PATH are separated by a : character...

LINQ provides a built-in function for checking the equality of two IEnumerables, and that function can be used on arrays. The SequenceEqual function will return true if the arrays have the same length and the values in corresponding indices are equal, and false otherwise. int[] arr1 = { 3, 5, 7 };...

Consider this example function to check if a host is up: is_alive() { ping -c1 "$1" &> /dev/null } This function sends a single ping to the host specified by the first function parameter. The output and error output of ping are both redirected to /dev/null, so the functi...

Decorator is one of structural design patterns. It is used to add, remove or change behaviour of object. This document will teach you how to use Decorator DP properly. Let me explain the idea of it to you on a simple example. Imagine you're now in Starbobs, famous coffee company. You can place an o...

ssh -p 21 [email protected] <<EOF echo 'printing pwd' echo "\$(pwd)" ls -a find '*.txt' EOF $ is escaped because we do not want it to be expanded by the current shell i.e $(pwd) is to be executed on the remote shell. Another way: ssh -p 21 [email protected] <...

sudo -s <<EOF a='var' echo 'Running serveral commands with sudo' mktemp -d echo "\$a" EOF $a needs to be escaped to prevent it to be expanded by the current shell Or sudo -s <<'EOF' a='var' echo 'Running serveral commands with sudo' mktemp -d e...

Detailed instructions on getting google-bigquery set up or installed.

IRB means "Interactive Ruby Shell", letting us execute ruby expressions from the standart input. To start, type irb into your shell. You can write anything in Ruby, from simple expressions: $ irb 2.1.4 :001 > 2+2 => 4 to complex cases like methods: 2.1.4 :001> def method ...

Inside your layout, add a Login button with the following code: <com.twitter.sdk.android.core.identity.TwitterLoginButton android:id="@+id/twitter_login_button" android:layout_width="wrap_content" android:layout_height="wrap_content" and...

The class use Phalcon\Validation\Validator; use Phalcon\Validation\ValidatorInterface; use Phalcon\Validation\Message; class RecaptchaValidator extends Validator implements ValidatorInterface { public function validate(\Phalcon\Validation $validation, $attribute) { $value =...

Things you need A paid Apple Developer Program Membership A valid App ID and identifier for you app (like com.example.MyApp) which is not used before anywhere Access to developer.apple.com and Member Center An iOS Device to test (as Push Notifications don't work on Simulator) Enabling t...

You can find description of the driver here. The quick example is: import psycopg2 db_host = 'postgres.server.com' db_port = '5432' db_un = 'user' db_pw = 'password' db_name = 'testdb' conn = psycopg2.connect("dbname={} host={} user={} password={}".format( ...

An extremely simple tool for installing PostgreSQL on a Mac is available by downloading Postgres.app. You can change preferences to have PostgreSQL run in the background or only when the application is running.

In order to determine some simple statistics of a value in a column of a table, you can use an aggregate function. If your individuals table is: NameAgeAllie17Amanda14Alana20 You could write this statement to get the minimum, maximum and average value: SELECT min(age), max(age), avg(age) FROM i...

In order to use Gson you have to include it in your project. You can do this by adding the following dependency of the Gson version available in Maven Central: Maven Add to pom.xml <dependencies> <dependency> <groupId>com.google.code.gson</groupId> <a...

C++ compilers encode additional information in the names of exported functions, such as argument types, to make overloads with different arguments possible. This process is called name mangling. This causes problems with importing functions in C# (and interop with other languages in general), as the...

There're several conventions of calling functions, specifying who (caller or callee) pops arguments from the stack, how arguments are passed and in what order. C++ uses Cdecl calling convention by default, but C# expects StdCall, which is usually used by Windows API. You need to change one or the ot...