FFIExamples.jl: Simple Examples Of Julia's FFI As Of V0.4

FFIExamples.jl

Many small examples that demonstrate how Julia's FFI works as of v0.4.

Examples

001: Pass a Float64 from Julia to C by copying the value. Return a Float64 from C to Julia by copying the value.

002: Pass a Float64 from Julia to C by copying a reference to the value. Return a Void value from C to Julia as a no-op.

003: Pass an ASCIIString from Julia to C by copying a reference to the string's raw bytes. Mutate the raw byte vector inside the C function. Return a Void value from C to Julia as a no-op.

004: Pass no arguments to a C function that returns a pointer to a static Vector{Uint8} whose memory is owned by C. Make a copy of the vector and interpret it as a string using bytestring. This creates an ASCIIString value that Julia's GC will free when appropriate.

005: Pass a primitive integer type from Julia to C by copying the value. Return a user-defined isbits immutable struct by copying the value. Note that both Julia and C need to define the struct independently, but using equivalent memory layouts.

006: Pass a user-defined isbits immutable struct from Julia to C by copying the value. Return a primitive integer type by copying the result value.

007: Pass a user-defined mutable struct from Julia to C by copying a reference to the value. Mutate the struct's contents in C. Return Void.

008: Pass a primitive integer type from Julia to C by coping the value. Return a user-defined mutable struct by copying the value.

009: Pass a vector of primitive floating point type from Julia to C by copying a reference to the vector along with a copy of the array's length as a primitive integer type. Mutate the array in C. Return Void.

010: Pass a vector of vectors of primitive floating point type from Julia to C by copying a reference to the vector of vectors along with a copy of the outer vector's length and a copy of the inner vector's common length. Mutate each of the inner vectors in C. Return Void.

011: Pass a vector of ASCIIString objects from Julia to C by copying a reference to a vector of strings long with a copy of the outer vector's length and a reference to a vector of primitive integers, each of which represents the length of an individual string in the vector. Mutate each string in C. Return Void.

012: Pass a vector of user-defined immutable structs from Julia to C by copying a reference to the vector along with a copy of the vector's length as a primitive integer value. Mutate each of the structs in C, thereby violating Julia's internal-to-Julia requirement that immutable objects never be mutated. Return Void.

Download Details:

Author: johnmyleswhite
Source Code: https://github.com/johnmyleswhite/FFIExamples.j l
License: View license

#julia #examples 

FFIExamples.jl: Simple Examples Of Julia's FFI As Of V0.4

Examples of the curl command in Linux

URL Syntax
The URL syntax is completely protocol-dependent with cURL. Before reading more about parameters or example, you must know the URL formats, you can use with curl.
CURL Command Options
curl command comes with large number of command line options. Which provides it great flexibility to perform various tasks. Here we will describe you some frequently used command options with curl command.

#linux commands #curl #examples #linux

Examples of the curl command in Linux

Examples of how to use the lsof command in Linux

Below are some of the popular usage of the lsof command.

  1. List all open files
  2. List by filename
  3. List open files by username
  4. List open files by process
  5. List open files by PID
  6. List open files containing directory
  7. Repeat mode
  8. List open files with network protocol
  9. List open files by port
  10. List open files by IPv4/IPv6
  11. List open files on NFS
  12. List locked deleted files

#linux #command #lsof command #examples

Examples of how to use the lsof command in Linux
Grace  Lesch

Grace Lesch

1623470247

Disaster Recovery Examples

Setup Movr With a Bad Actor Record
For this example, we’ll create a MOVR workload and show how to recover from a malicious attack from a user called devil. On the MOVR rides table, let’s activate an audit log so we can see all of the SQL transactions that incur on the table. While the workload is running, we’ll inject the rogue user called devil and have that user create a malicious transaction that updates all of Tyler Dalton’s transactions to be $1000.

#database #disaster #recovery #examples

Disaster Recovery Examples
Delbert  Ferry

Delbert Ferry

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Hacking GraphQL for Fun and Profit — Part 2— Methodology and Examples

I am back with another part of the Hacking GraphQL series. We have already gone through basics in the previous post. I highly recommend you to go through the post, if not already. In this blog we will go through a demo application called Generic University created by awesome InsiderPHD to understand some basic bugs and craft a methodology to test GraphQL.
Vulnerabilities in GraphQL Implementation
Let’s cut to the chase and come straight to the point, all the bugs which can be found in REST APIs can be found in the GraphQL.

#graphql #hacking #fun and profit #methodology #examples

Hacking GraphQL for Fun and Profit — Part 2— Methodology and Examples
Justin Brooks

Justin Brooks

1601990040

3 Examples of using Proxy and Reflect API in JavaScript

Not sure what a Proxy is or how to use it in JavaScript? In this video, we take a look at 3 different examples of using a proxy which may be useful in any full-stack application. We also take a look at the Reflect API and how it can help when using the proxy API.

⭐ TIMESTAMPS ⭐
0:00 - Introduction
0:19 - Basic Overview of Proxy
0:49 - Example 1: Logging access to an object
1:18 - Proxy vs Reflect
1:53 - Example 2: Custom error handling
2:35 - Example 3: String utility proxy
3:18 - Conclusion

⚡ RESOURCES ⚡
Proxy API Documentation - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Proxy
Reflect API Documentation - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect

#javascript #proxy #examples

3 Examples of using Proxy and Reflect API in JavaScript
Christa  Stehr

Christa Stehr

1594697940

11: Include and Require in PHP | Procedural PHP Tutorial For Beginners

In this PHP tutorial video I will teach you about including files in PHP, and give you some actual practical examples of how we use it on websites.

➤ GET ACCESS TO MY LESSON MATERIAL HERE!

First of all, thank you for all the support you have given me!

I am really glad to have such an awesome community on my channel. It motivates me to continue creating and uploading content! So thank you!

I am now using Patreon to share improved and updated lesson material, and for a small fee you can access all the material. I have worked hard, and done my best to help you understand what I teach.

#php #examples

11: Include and Require in PHP | Procedural PHP Tutorial For Beginners
Christa  Stehr

Christa Stehr

1594604760

Closures with examples

Closure is of the most beautiful and sometimes intricate part to understand in Javascipt. In simple words, a closure gives you access to an outer function’s scope from an inner function.

Closures allow us to invoke an inner function outside its enclosing function while maintaining access to the enclosing function’s lexical scope(i.e identifiers in its enclosing function).

See this example to better understand:

function outer(){ 
    let value =10;
    return function(){
        console.log(value);
    }
}
const innerFunction = outer();
innerFunction();// 10

We define an outer function and return a function from it. Here the returned function is a higher order function.

We call the outer function and store it in innerFunction variable. innerFunction retains the value even after the outer function has returned. That’s closures in action.

Functions are first class citizens in javascript. Functions that operate on other functions, either by taking them as arguments or by returning them, are called higher-order functions.

Let’s see closures in action with examples.


1. How many times a function is called?

function outer() {
	  let counter = 0;
	  return function incrementCounter () {
	    counter++;
	    console.log(`Called ${counter} times`);
	  }
	}

	const increment = outer();
	increment(); // Called 1 times
	increment(); // Called 2 times
	increment(); // Called 3 times

Examine the code for the outer function. Notice that we are returning a function and that function is using counter variable that’s outside of its scope. Closure is how we access the variable from the outer scope.

#ui #javascript #closure #examples

Closures with examples

How to Set Up and Manage Sudo Permissions

Sudo is a Linux program meant to allow a user to use root privileges for a limited timeframe to users and log root activity. The basic thought is to give as few privileges as possible to a user while allowing the user to accomplish a task. The term “Sudo” means substitute user, and do. It is a program used for managing of user permission based on a system configuration file. It allows users to run programs with the privileges of another user, by default, the superuser. The program is supplied for most UNIX and Linux-based operating systems.

#tutorials #alias #centos #configuration #debug #elevated permissions #examples #group #host #logging #nano #permission sets #permissions #privileges #root #subsystem #sudo #sudoers #superuser #terminal #ubuntu #vim #visudo

How to Set Up and Manage Sudo Permissions