Tutorial by Examples: f

If you want to extract a folder, but you want to exclude one or several folders during the extraction, you can use the --exclude option. tar -cf archive.tar ./my-folder/ --exclude="my-folder/sub1" --exclude="my-folder/sub3" With this folder tree : my-folder/ sub1/ su...

$ fg %2 sleep 600 %2 specifies job no. 2. If fg is used without any arguments if brings the last process put in background to the foreground. $ fg %?sle sleep 500 ?sle refers to the baground process command containing "sle". If multiple background commands contain the string, it w...

Press Ctrl + Z to stop a foreground process and put it in background $ sleep 600 ^Z [8]+ Stopped sleep 600

SELECT SERVERPROPERTY('ProductVersion') AS ProductVersion, SERVERPROPERTY('ProductLevel') AS ProductLevel, SERVERPROPERTY('Edition') AS Edition, SERVERPROPERTY('EngineEdition') AS EngineEdition;

If you know you need a packet <packet>, but you don't know the exact name <packet-exact-name>, instead of searching with Google try with the following: sudo apt-get update apt-cache search <packet> This will return you a list of packets name with a description. Once you have i...

You can create and configure build types in the module-level build.gradle file inside the android {} block. android { ... defaultConfig {...} buildTypes { release { minifyEnabled true proguardFiles getDefaultProguar...

<ItemGroup> <DataToCopy Include="*.cs;*.aspx" /> </ItemGroup> <Copy SourceFiles="@(DataToCopy)" DestinationFolder="SourceCopiedFolder" />

A Haskell's Functor allows one to map any type a (an object of Hask) to a type F a and also map a function a -> b (a morphism of Hask) to a function with type F a -> F b. This corresponds to a Category Theory definition in a sense that functor preserves basic category structure. A monoidal ca...

1067 This is probably related to TIMESTAMP defaults, which have changed over time. See TIMESTAMP defaults in the Dates & Times page. (which does not exist yet) 1292/1366 DOUBLE/Integer Check for letters or other syntax errors. Check that the columns align; perhaps you think you are putting i...

In some cases basic validation is not enough. Angular support custom validation adding validator functions to the $validators object on the ngModelController: angular.module('app', []) .directive('myValidator', function() { return { // element must have ng-model attribute // o...

It may be helpful to include additional information with an exception, e.g. for logging purposes or to allow conditional handling when the exception is caught: class CustomError < StandardError attr_reader :safe_to_retry def initialize(safe_to_retry = false, message = 'Something went wro...

fork() is a system call. fork is used to create a child process from the running process, which is a replica of the parent process(Process which executed fork() ). Child process is derived from the parent process. Both the parent and child have different address space, each is independent of the cha...

If you want to set some alias name to installed node version, do: nvm alias <name> <version> Similary to unalias, do: nvm unalias <name> A proper usecase would be, if you want to set some other version than stable version as default alias. default aliased versions are loade...

There are several ways of getting the data that you will bind to the DOM elements. The simpler one is having your data in your script as an array... var data = [ ... ]; But D3.js allows us to load data from an external file. In this example, we will see how to properly load and deal with data fr...

You can allow role to access some action on resource by: $acl->allow('Administrator', 'products', 'create'); You can deny role to access some action on resource by: $acl->deny('Customer', 'categories', 'create'); You can check if role is allowed to some action on resource by using: $a...

Modifying the strings returned by the standard functions getenv(), strerror() and setlocale() is undefined. So, implementations may use static storage for these strings. The getenv() function, C11, §7.22.4.7, 4, says: The getenv function returns a pointer to a string associated with the matched...

To execute a function within a loop in node.js, it's fine to use a for loop for short loops. But the loop is long, using for loop will increase the time of processing which might cause the node process to hang. In such scenarios, you can use: asycn.times function recursiveAction(n, callback) { ...

When we want to handle array of data, its better to use async.each. When we want to perform something with all data & want to get the final callback once everything is done, then this method will be useful. This is handled in parallel way. function createUser(userName, callback) { //creat...

var path = "/test_javascript_upload.txt"; var content = "data to upload"; var accessToken = "<ACCESS_TOKEN>"; var uploadUrl = "https://content.dropboxapi.com/2/files/upload" var result; var xhr = new XMLHttpRequest(); xhr.onreadystatechange = fun...

If you have a greedy match as the first quantifier, the whole RE will be greedy, If you have non-greedy match as the first quantifier, the whole RE will be non-greedy. set mydata { Device widget1: port: 156 alias: input2 Device widget2: alias: input1 Device widget3: port: 238 alias...