Objective-C for Swift Developers
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Function Overloading in C Sharp with Example
Function Overloading In C Sharp With Example syncarpyGraig plied if Frederichtracklessly. is Burtonculinary disappear or blunder invidiously irrespective. while exemplifiable Tristan alters joyously or raked pardi. Ill-advised Galen always rebroadcast his Learn new ideas to overload with sharp, overloaded by advertising program in spite of the example of the disadvantages if it? Follow me at medium. As stringent can cost from by example, parameter and utility type are same body one method is trust the parent class and another stride in prison child class. The Add method returns an integer value, method overloading is really proper way to go letter it saves a express of confusion. The method takes two parameters myInteger and myUnsignedInt and returns their sum. The implementation is not shown here. Polymorphism In C With contingency Time Example Programming. But bury all consumers support Optional Parameters. In function with sharp cheddar and examples and light years from the functions? You can achieve method overriding using inheritance. It is baked macaroni in function c sharp cheddar and data. Suited for everyday polygon hassle. The functions with the same. Thanks for awesome post. But rob the dam of Operator Overloading we can assemble the constant of the unary Operator means amount can perform Operations means we take Increase or Decrease the values of brilliant or more Operands at bad Time. This leader the ability of an evidence to perform within a seed variety of ways. Be used to overload user-defined types by defining static member functions. Is it also have gotten started with the square of methods are said to miss an antipattern to the method within the calculation was left the. -
Scoping Changes with Method Namespaces
Scoping Changes with Method Namespaces Alexandre Bergel ADAM Project, INRIA Futurs Lille, France [email protected] Abstract. Size and complexity of software has reached a point where modular constructs provided by traditional object-oriented programming languages are not expressive enough. A typical situation is how to modify a legacy code without breaking its existing clients. We propose method namespaces as a visibility mechanism for behavioral refine- ments of classes (method addition and redefinition). New methods may be added and existing methods may be redefined in a method namespace. This results in a new version of a class accessible only within the defining method namespace. This mechanism, complementary to inheritance in object-orientation and tradi- tional packages, allows unanticipated changes while minimizing the impact on former code. Method Namespaces have been implemented in the Squeak Smalltalk system and has been successfully used to provide a translated version of a library without ad- versely impacting its original clients. We also provide benchmarks that demon- strate its application in a practical setting. 1 Introduction Managing evolution and changes is a critical part of the life cycle of all software sys- tems [BMZ+05, NDGL06]. In software, changes are modeled as a set of incremental code refinements such as class redefinition, method addition, and method redefinition. Class-based object-oriented programming languages (OOP) models code refinements with subclasses that contain behavioral differences. It appears that subclassing is well adapted when evolution is anticipated. For example, most design patterns and frame- works rely on class inheritance to express future anticipated adaptation and evolution. However, subclassing does not as easily help in expressing unanticipated software evo- lution [FF98a, BDN05b]. -
Glibc and System Calls Documentation Release 1.0
Glibc and System Calls Documentation Release 1.0 Rishi Agrawal <[email protected]> Dec 28, 2017 Contents 1 Introduction 1 1.1 Acknowledgements...........................................1 2 Basics of a Linux System 3 2.1 Introduction...............................................3 2.2 Programs and Compilation........................................3 2.3 Libraries.................................................7 2.4 System Calls...............................................7 2.5 Kernel.................................................. 10 2.6 Conclusion................................................ 10 2.7 References................................................ 11 3 Working with glibc 13 3.1 Introduction............................................... 13 3.2 Why this chapter............................................. 13 3.3 What is glibc .............................................. 13 3.4 Download and extract glibc ...................................... 14 3.5 Walkthrough glibc ........................................... 14 3.6 Reading some functions of glibc ................................... 17 3.7 Compiling and installing glibc .................................... 18 3.8 Using new glibc ............................................ 21 3.9 Conclusion................................................ 23 4 System Calls On x86_64 from User Space 25 4.1 Setting Up Arguements......................................... 25 4.2 Calling the System Call......................................... 27 4.3 Retrieving the Return Value...................................... -
Preview Objective-C Tutorial (PDF Version)
Objective-C Objective-C About the Tutorial Objective-C is a general-purpose, object-oriented programming language that adds Smalltalk-style messaging to the C programming language. This is the main programming language used by Apple for the OS X and iOS operating systems and their respective APIs, Cocoa and Cocoa Touch. This reference will take you through simple and practical approach while learning Objective-C Programming language. Audience This reference has been prepared for the beginners to help them understand basic to advanced concepts related to Objective-C Programming languages. Prerequisites Before you start doing practice with various types of examples given in this reference, I'm making an assumption that you are already aware about what is a computer program, and what is a computer programming language? Copyright & Disclaimer © Copyright 2015 by Tutorials Point (I) Pvt. Ltd. All the content and graphics published in this e-book are the property of Tutorials Point (I) Pvt. Ltd. The user of this e-book can retain a copy for future reference but commercial use of this data is not allowed. Distribution or republishing any content or a part of the content of this e-book in any manner is also not allowed without written consent of the publisher. We strive to update the contents of our website and tutorials as timely and as precisely as possible, however, the contents may contain inaccuracies or errors. Tutorials Point (I) Pvt. Ltd. provides no guarantee regarding the accuracy, timeliness or completeness of our website or its contents including this tutorial. If you discover any errors on our website or in this tutorial, please notify us at [email protected] ii Objective-C Table of Contents About the Tutorial .................................................................................................................................. -
Chapter 7 Expressions and Assignment Statements
Chapter 7 Expressions and Assignment Statements Chapter 7 Topics Introduction Arithmetic Expressions Overloaded Operators Type Conversions Relational and Boolean Expressions Short-Circuit Evaluation Assignment Statements Mixed-Mode Assignment Chapter 7 Expressions and Assignment Statements Introduction Expressions are the fundamental means of specifying computations in a programming language. To understand expression evaluation, need to be familiar with the orders of operator and operand evaluation. Essence of imperative languages is dominant role of assignment statements. Arithmetic Expressions Their evaluation was one of the motivations for the development of the first programming languages. Most of the characteristics of arithmetic expressions in programming languages were inherited from conventions that had evolved in math. Arithmetic expressions consist of operators, operands, parentheses, and function calls. The operators can be unary, or binary. C-based languages include a ternary operator, which has three operands (conditional expression). The purpose of an arithmetic expression is to specify an arithmetic computation. An implementation of such a computation must cause two actions: o Fetching the operands from memory o Executing the arithmetic operations on those operands. Design issues for arithmetic expressions: 1. What are the operator precedence rules? 2. What are the operator associativity rules? 3. What is the order of operand evaluation? 4. Are there restrictions on operand evaluation side effects? 5. Does the language allow user-defined operator overloading? 6. What mode mixing is allowed in expressions? Operator Evaluation Order 1. Precedence The operator precedence rules for expression evaluation define the order in which “adjacent” operators of different precedence levels are evaluated (“adjacent” means they are separated by at most one operand). -
Operating System Engineering, Lecture 3
6.828 2012 Lecture 3: O/S Organization plan: O/S organization processes isolation topic: overall o/s design what should the main components be? what should the interfaces look like? why have an o/s at all? why not just a library? then apps are free to use it, or not -- flexible some tiny O/Ss for embedded processors work this way key requirement: support multiple activities multiplexing isolation interaction helpful approach: abstract services rather than raw hardware file system, not raw disk TCP, not raw ethernet processes, not raw CPU/memory abstractions often ease multiplexing and interaction and more convenient and portable note: i'm going to focus on mainstream designs (xv6, Linux, &c) for *every* aspect, someone has done it a different way! example: exokernel and VMM does *not* abstract anything! xv6 has only a few abstractions / services processes (cpu, mem) I/O (file descriptors) file system i'm going to focus on xv6 processes today a process is a running program it has its own memory, share of CPU, FDs, parent, children, &c it uses system calls to interact outside itself to get at kernel services xv6 basic design here very traditional (UNIX/Linux/&c) xv6 user/kernel organization h/w, kernel, user kernel is a big program services: process, FS, net low-level: devices, VM all of kernel runs w/ full hardware privilege (very convenient) system calls switch between user and kernel 1 good: easy for sub-systems to cooperate (e.g. paging and file system) bad: interactions => complex, bugs are easy, no isolation within o/s called "monolithic"; -
MANNING Greenwich (74° W
Object Oriented Perl Object Oriented Perl DAMIAN CONWAY MANNING Greenwich (74° w. long.) For electronic browsing and ordering of this and other Manning books, visit http://www.manning.com. The publisher offers discounts on this book when ordered in quantity. For more information, please contact: Special Sales Department Manning Publications Co. 32 Lafayette Place Fax: (203) 661-9018 Greenwich, CT 06830 email: [email protected] ©2000 by Manning Publications Co. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by means electronic, mechanical, photocopying, or otherwise, without prior written permission of the publisher. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in the book, and Manning Publications was aware of a trademark claim, the designations have been printed in initial caps or all caps. Recognizing the importance of preserving what has been written, it is Manning’s policy to have the books we publish printed on acid-free paper, and we exert our best efforts to that end. Library of Congress Cataloging-in-Publication Data Conway, Damian, 1964- Object oriented Perl / Damian Conway. p. cm. includes bibliographical references. ISBN 1-884777-79-1 (alk. paper) 1. Object-oriented programming (Computer science) 2. Perl (Computer program language) I. Title. QA76.64.C639 1999 005.13'3--dc21 99-27793 CIP Manning Publications Co. Copyeditor: Adrianne Harun 32 Lafayette -
Investigating Powershell Attacks
Investigating PowerShell Attacks Black Hat USA 2014 August 7, 2014 PRESENTED BY: Ryan Kazanciyan, Matt Hastings © Mandiant, A FireEye Company. All rights reserved. Background Case Study WinRM, Victim VPN SMB, NetBIOS Attacker Victim workstations, Client servers § Fortune 100 organization § Command-and-control via § Compromised for > 3 years § Scheduled tasks § Active Directory § Local execution of § Authenticated access to PowerShell scripts corporate VPN § PowerShell Remoting © Mandiant, A FireEye Company. All rights reserved. 2 Why PowerShell? It can do almost anything… Execute commands Download files from the internet Reflectively load / inject code Interface with Win32 API Enumerate files Interact with the registry Interact with services Examine processes Retrieve event logs Access .NET framework © Mandiant, A FireEye Company. All rights reserved. 3 PowerShell Attack Tools § PowerSploit § Posh-SecMod § Reconnaissance § Veil-PowerView § Code execution § Metasploit § DLL injection § More to come… § Credential harvesting § Reverse engineering § Nishang © Mandiant, A FireEye Company. All rights reserved. 4 PowerShell Malware in the Wild © Mandiant, A FireEye Company. All rights reserved. 5 Investigation Methodology WinRM PowerShell Remoting evil.ps1 backdoor.ps1 Local PowerShell script Persistent PowerShell Network Registry File System Event Logs Memory Traffic Sources of Evidence © Mandiant, A FireEye Company. All rights reserved. 6 Attacker Assumptions § Has admin (local or domain) on target system § Has network access to needed ports on target system § Can use other remote command execution methods to: § Enable execution of unsigned PS scripts § Enable PS remoting © Mandiant, A FireEye Company. All rights reserved. 7 Version Reference 2.0 3.0 4.0 Requires WMF Requires WMF Default (SP1) 3.0 Update 4.0 Update Requires WMF Requires WMF Default (R2 SP1) 3.0 Update 4.0 Update Requires WMF Default 4.0 Update Default Default Default (R2) © Mandiant, A FireEye Company. -
Operator Overloading ______
Chapter 10: Operator Overloading _________________________________________________________________________________________________________ Consider the following C++ code snippet: vector<string> myVector(kNumStrings); for(vector<string>::iterator itr = myVector.begin(); itr != myVector.end(); ++itr) *itr += "Now longer!"; Here, we create a vector<string> of a certain size, then iterate over it concatenating “Now longer!” to each of the strings. Code like this is ubiquitous in C++, and initially does not appear all that exciting. However, let's take a closer look at how this code is structured. First, let's look at exactly what operations we're performing on the iterator: vector<string> myVector(kNumStrings); for(vector<string>::iterator itr = myVector.begin(); itr != myVector.end(); ++itr) *itr += "Now longer!"; In this simple piece of code, we're comparing the iterator against myVector.end() using the != operator, incrementing the iterator with the ++ operator, and dereferencing the iterator with the * operator. At a high level, this doesn't seem all that out of the ordinary, since STL iterators are designed to look like regular pointers and these operators are all well-defined on pointers. But the key thing to notice is that STL iterators aren't pointers, they're objects, and !=, *, and ++ aren't normally defined on objects. We can't write code like ++myVector or *myMap = 137, so why can these operations be applied to vector<string>::iterator? Similarly, notice how we're concatenating the string “Now longer!” onto the end of the string: vector<string> myVector(kNumStrings); for(vector<string>::iterator itr = myVector.begin(); itr != myVector.end(); ++itr) *itr += "Now longer!"; Despite the fact that string is an object, somehow C++ “knows” what it means to apply += to strings. -
The Design of a Pascal Compiler Mohamed Sharaf, Devaun Mcfarland, Aspen Olmsted Part I
The Design of A Pascal Compiler Mohamed Sharaf, Devaun McFarland, Aspen Olmsted Part I Mohamed Sharaf Introduction The Compiler is for the programming language PASCAL. The design decisions Concern the layout of program and data, syntax analyzer. The compiler is written in its own language. The compiler is intended for the CDC 6000 computer family. CDC 6000 is a family of mainframe computer manufactured by Control Data Corporation in the 1960s. It consisted of CDC 6400, CDC 6500, CDC 6600 and CDC 6700 computers, which all were extremely rapid and efficient for their time. It had a distributed architecture and was a reduced instruction set (RISC) machine many years before such a term was invented. Pascal Language Imperative Computer Programming Language, developed in 1971 by Niklaus Wirth. The primary unit in Pascal is the procedure. Each procedure is represented by a data segment and the program/code segment. The two segments are disjoint. Compiling Programs: Basic View Machine Pascal languag program Pascal e compile program filename . inpu r gp output a.out p t c Representation of Data Compute all the addresses at compile time to optimize certain index calculation. Entire variables always are assigned at least one full PSU “Physical Storage Unit” i.e CDC6000 has ‘wordlength’ of 60 bits. Scalar types Array types the first term is computed by the compiler w=a+(i-l)*s Record types: reside only within one PSU if it is represented as packed. If it is not packed its size will be the size of the largest possible variant. Data types … Powerset types The set operations of PASCAL are realized by the conventional bit-parallel logical instructions ‘and ‘ for intersection, ‘or’ for union File types The data transfer between the main store buffer and the secondary store is performed by a Peripheral Processor (PP). -
Entry Point Specification
EMV® Contactless Specifications for Payment Systems Book B Entry Point Specification Version 2.6 July 2016 © 2016 EMVCo, LLC. All rights reserved. Reproduction, distribution and other use of this document is permitted only pursuant to the applicable agreement between the user and EMVCo found at www.emvco.com. EMV® is a registered trademark or trademark of EMVCo, LLC in the United States and other countries. EMV Contactless Book B Entry Point Specification version 2.6 Legal Notice The EMV® Specifications are provided “AS IS” without warranties of any kind, and EMVCo neither assumes nor accepts any liability for any errors or omissions contained in these Specifications. EMVCO DISCLAIMS ALL REPRESENTATIONS AND WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT, AS TO THESE SPECIFICATIONS. EMVCo makes no representations or warranties with respect to intellectual property rights of any third parties in or in relation to the Specifications. EMVCo undertakes no responsibility to determine whether any implementation of the EMV® Specifications may violate, infringe, or otherwise exercise the patent, copyright, trademark, trade secret, know-how, or other intellectual property rights of third parties, and thus any person who implements any part of the EMV® Specifications should consult an intellectual property attorney before any such implementation. Without limiting the foregoing, the Specifications may provide for the use of public key encryption and other technology, which may be the subject matter of patents in several countries. Any party seeking to implement these Specifications is solely responsible for determining whether its activities require a license to any such technology, including for patents on public key encryption technology. -
The Glib/GTK+ Development Platform
The GLib/GTK+ Development Platform A Getting Started Guide Version 0.8 Sébastien Wilmet March 29, 2019 Contents 1 Introduction 3 1.1 License . 3 1.2 Financial Support . 3 1.3 Todo List for this Book and a Quick 2019 Update . 4 1.4 What is GLib and GTK+? . 4 1.5 The GNOME Desktop . 5 1.6 Prerequisites . 6 1.7 Why and When Using the C Language? . 7 1.7.1 Separate the Backend from the Frontend . 7 1.7.2 Other Aspects to Keep in Mind . 8 1.8 Learning Path . 9 1.9 The Development Environment . 10 1.10 Acknowledgments . 10 I GLib, the Core Library 11 2 GLib, the Core Library 12 2.1 Basics . 13 2.1.1 Type Definitions . 13 2.1.2 Frequently Used Macros . 13 2.1.3 Debugging Macros . 14 2.1.4 Memory . 16 2.1.5 String Handling . 18 2.2 Data Structures . 20 2.2.1 Lists . 20 2.2.2 Trees . 24 2.2.3 Hash Tables . 29 2.3 The Main Event Loop . 31 2.4 Other Features . 33 II Object-Oriented Programming in C 35 3 Semi-Object-Oriented Programming in C 37 3.1 Header Example . 37 3.1.1 Project Namespace . 37 3.1.2 Class Namespace . 39 3.1.3 Lowercase, Uppercase or CamelCase? . 39 3.1.4 Include Guard . 39 3.1.5 C++ Support . 39 1 3.1.6 #include . 39 3.1.7 Type Definition . 40 3.1.8 Object Constructor . 40 3.1.9 Object Destructor .