Writing PHP Extensions
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
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 .................................................................................................................................. -
Memory Management and Garbage Collection
Overview Memory Management Stack: Data on stack (local variables on activation records) have lifetime that coincides with the life of a procedure call. Memory for stack data is allocated on entry to procedures ::: ::: and de-allocated on return. Heap: Data on heap have lifetimes that may differ from the life of a procedure call. Memory for heap data is allocated on demand (e.g. malloc, new, etc.) ::: ::: and released Manually: e.g. using free Automatically: e.g. using a garbage collector Compilers Memory Management CSE 304/504 1 / 16 Overview Memory Allocation Heap memory is divided into free and used. Free memory is kept in a data structure, usually a free list. When a new chunk of memory is needed, a chunk from the free list is returned (after marking it as used). When a chunk of memory is freed, it is added to the free list (after marking it as free) Compilers Memory Management CSE 304/504 2 / 16 Overview Fragmentation Free space is said to be fragmented when free chunks are not contiguous. Fragmentation is reduced by: Maintaining different-sized free lists (e.g. free 8-byte cells, free 16-byte cells etc.) and allocating out of the appropriate list. If a small chunk is not available (e.g. no free 8-byte cells), grab a larger chunk (say, a 32-byte chunk), subdivide it (into 4 smaller chunks) and allocate. When a small chunk is freed, check if it can be merged with adjacent areas to make a larger chunk. Compilers Memory Management CSE 304/504 3 / 16 Overview Manual Memory Management Programmer has full control over memory ::: with the responsibility to manage it well Premature free's lead to dangling references Overly conservative free's lead to memory leaks With manual free's it is virtually impossible to ensure that a program is correct and secure. -
Strings in C++
Programming Abstractions C S 1 0 6 X Cynthia Lee Today’s Topics Introducing C++ from the Java Programmer’s Perspective . Absolute value example, continued › C++ strings and streams ADTs: Abstract Data Types . Introduction: What are ADTs? . Queen safety example › Grid data structure › Passing objects by reference • const reference parameters › Loop over “neighbors” in a grid Strings in C++ STRING LITERAL VS STRING CLASS CONCATENATION STRING CLASS METHODS 4 Using cout and strings int main(){ int n = absoluteValue(-5); string s = "|-5|"; s += " = "; • This prints |-5| = 5 cout << s << n << endl; • The + operator return 0; concatenates strings, } and += works in the way int absoluteValue(int n) { you’d expect. if (n<0){ n = -n; } return n; } 5 Using cout and strings int main(){ int n = absoluteValue(-5); But SURPRISE!…this one string s = "|-5|" + " = "; doesn’t work. cout << s << n << endl; return 0; } int absoluteValue(int n) { if (n<0){ n = -n; } return n; } C++ string objects and string literals . In this class, we will interact with two types of strings: › String literals are just hard-coded string values: • "hello!" "1234" "#nailedit" • They have no methods that do things for us • Think of them like integer literals: you can’t do "4.add(5);" //no › String objects are objects with lots of helpful methods and operators: • string s; • string piece = s.substr(0,3); • s.append(t); //or, equivalently: s+= t; String object member functions (3.2) Member function name Description s.append(str) add text to the end of a string s.compare(str) return -
Memory Management with Explicit Regions by David Edward Gay
Memory Management with Explicit Regions by David Edward Gay Engineering Diploma (Ecole Polytechnique F´ed´erale de Lausanne, Switzerland) 1992 M.S. (University of California, Berkeley) 1997 A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Computer Science in the GRADUATE DIVISION of the UNIVERSITY of CALIFORNIA at BERKELEY Committee in charge: Professor Alex Aiken, Chair Professor Susan L. Graham Professor Gregory L. Fenves Fall 2001 The dissertation of David Edward Gay is approved: Chair Date Date Date University of California at Berkeley Fall 2001 Memory Management with Explicit Regions Copyright 2001 by David Edward Gay 1 Abstract Memory Management with Explicit Regions by David Edward Gay Doctor of Philosophy in Computer Science University of California at Berkeley Professor Alex Aiken, Chair Region-based memory management systems structure memory by grouping objects in regions under program control. Memory is reclaimed by deleting regions, freeing all objects stored therein. Our compiler for C with regions, RC, prevents unsafe region deletions by keeping a count of references to each region. RC's regions have advantages over explicit allocation and deallocation (safety) and traditional garbage collection (better control over memory), and its performance is competitive with both|from 6% slower to 55% faster on a collection of realistic benchmarks. Experience with these benchmarks suggests that modifying many existing programs to use regions is not difficult. An important innovation in RC is the use of type annotations that make the structure of a program's regions more explicit. These annotations also help reduce the overhead of reference counting from a maximum of 25% to a maximum of 12.6% on our benchmarks. -
Architectural Support for Scripting Languages
Architectural Support for Scripting Languages By Dibakar Gope A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Electrical and Computer Engineering) at the UNIVERSITY OF WISCONSIN–MADISON 2017 Date of final oral examination: 6/7/2017 The dissertation is approved by the following members of the Final Oral Committee: Mikko H. Lipasti, Professor, Electrical and Computer Engineering Gurindar S. Sohi, Professor, Computer Sciences Parameswaran Ramanathan, Professor, Electrical and Computer Engineering Jing Li, Assistant Professor, Electrical and Computer Engineering Aws Albarghouthi, Assistant Professor, Computer Sciences © Copyright by Dibakar Gope 2017 All Rights Reserved i This thesis is dedicated to my parents, Monoranjan Gope and Sati Gope. ii acknowledgments First and foremost, I would like to thank my parents, Sri Monoranjan Gope, and Smt. Sati Gope for their unwavering support and encouragement throughout my doctoral studies which I believe to be the single most important contribution towards achieving my goal of receiving a Ph.D. Second, I would like to express my deepest gratitude to my advisor Prof. Mikko Lipasti for his mentorship and continuous support throughout the course of my graduate studies. I am extremely grateful to him for guiding me with such dedication and consideration and never failing to pay attention to any details of my work. His insights, encouragement, and overall optimism have been instrumental in organizing my otherwise vague ideas into some meaningful contributions in this thesis. This thesis would never have been accomplished without his technical and editorial advice. I find myself fortunate to have met and had the opportunity to work with such an all-around nice person in addition to being a great professor. -
Variable Feature Usage Patterns in PHP
Variable Feature Usage Patterns in PHP Mark Hills East Carolina University, Greenville, NC, USA [email protected] Abstract—PHP allows the names of variables, classes, func- and classes at runtime. Below, we refer to these generally as tions, methods, and properties to be given dynamically, as variable features, and specifically as, e.g., variable functions expressions that, when evaluated, return an identifier as a string. or variable methods. While this provides greater flexibility for programmers, it also makes PHP programs harder to precisely analyze and understand. The main contributions presented in this paper are as follows. In this paper we present a number of patterns designed to First, taking advantage of our prior work, we have developed recognize idiomatic uses of these features that can be statically a number of patterns for detecting idiomatic uses of variable resolved to a precise set of possible names. We then evaluate these features in PHP programs and for resolving these uses to a patterns across a corpus of 20 open-source systems totaling more set of possible names. Written using the Rascal programming than 3.7 million lines of PHP, showing how often these patterns occur in actual PHP code, demonstrating their effectiveness at language [2], [3], these patterns work over the ASTs of the statically determining the names that can be used at runtime, PHP scripts, with more advanced patterns also taking advantage and exploring anti-patterns that indicate when the identifier of control flow graphs and lightweight analysis algorithms for computation is truly dynamic. detecting value flow and reachability. Each of these patterns works generally across all variable features, instead of being I. -
Strings String Literals String Variables Warning!
Strings String literals • Strings are not a built-in data type. char *name = "csc209h"; printf("This is a string literal\n"); • C provides almost no special means of defining or working with strings. • String literals are stored as character arrays, but • A string is an array of characters you can't change them. terminated with a “null character” ('\0') name[1] = 'c'; /* Error */ • The compiler reserves space for the number of characters in the string plus one to store the null character. 1 2 String Variables Warning! • arrays are used to store strings • Big difference between a string's length • strings are terminated by the null character ('\0') and size! (That's how we know a string's length.) – length is the number of non-null characters • Initializing strings: currently present in the string – char course[8] = "csc209h"; – size if the amount of memory allocated for – char course[8] = {'c','s','c',… – course is an array of characters storing the string – char *s = "csc209h"; • Eg., char s[10] = "abc"; – s is a pointer to a string literal – length of s = 3, size of s = 10 – ensure length+1 ≤ size! 3 4 String functions Copying a string • The library provides a bunch of string char *strncpy(char *dest, functions which you should use (most of the char *src, int size) time). – copy up to size bytes of the string pointed to by src in to dest. Returns a pointer to dest. $ man string – Do not use strcpy (buffer overflow problem!) • int strlen(char *str) – returns the length of the string. Remember that char str1[3]; the storage needed for a string is one plus its char str2[5] = "abcd"; length /*common error*/ strncpy(str1, str2, strlen(str2));/*wrong*/ 5 6 Concatenating strings Comparing strings char *strncat(char *s1, const char *s2, size_t n); int strcmp(const char *s1, const char *s2) – appends the contents of string s2 to the end of s1, and returns s1. -
Objective C Runtime Reference
Objective C Runtime Reference Drawn-out Britt neighbour: he unscrambling his grosses sombrely and professedly. Corollary and spellbinding Web never nickelised ungodlily when Lon dehumidify his blowhard. Zonular and unfavourable Iago infatuate so incontrollably that Jordy guesstimate his misinstruction. Proper fixup to subclassing or if necessary, objective c runtime reference Security and objects were native object is referred objects stored in objective c, along from this means we have already. Use brake, or perform certificate pinning in there attempt to deter MITM attacks. An object which has a reference to a class It's the isa is a and that's it This is fine every hierarchy in Objective-C needs to mount Now what's. Use direct access control the man page. This function allows us to voluntary a reference on every self object. The exception handling code uses a header file implementing the generic parts of the Itanium EH ABI. If the method is almost in the cache, thanks to Medium Members. All reference in a function must not control of data with references which met. Understanding the Objective-C Runtime Logo Table Of Contents. Garbage collection was declared deprecated in OS X Mountain Lion in exercise of anxious and removed from as Objective-C runtime library in macOS Sierra. Objective-C Runtime Reference. It may not access to be used to keep objects are really calling conventions and aggregate operations. Thank has for putting so in effort than your posts. This will cut down on the alien of Objective C runtime information. Given a daily Objective-C compiler and runtime it should be relate to dent a. -
Curriculum of Php
CETPA INFOTECH PVT. LTD. CURRICULUM OF PHP CORE PHP ARRAY WITH PHP PHP INPUT MACHANISM What is an Array? INTRODUCING PHP Working with ECHO, PRINT(), Creating and Working with PRINTF() Arrays The origin of PHP MINI TASK → Integrating Creating arrays PHP for Web Development & Web HTML Viewing arrays Applications with PHP Modifying arrays PHP History MINI TASK → Integrating CSS Removing values from arrays Features of PHP with PHP Sorting Arrays How PHP works with the MINI TASK → Integrating Walking through an Array Web Server JAVASCRIPT with PHP Traversing an array manually What is SERVER & how it Using foreach to walk through an Works BASICS LANGUAGE array What is ZEND Engine Creating a simple PHP script Finding Array Size Work of ZEND Engine Naming Variables Converting Arrays into Assigning and Displaying Strings (And Vice Versa) INSTALLING AND CONFIGURING Variable Converting Variables into PHP Values Arrays (And Vice Versa) ● PHP Installation Creating variables Splitting and Merging Arrays ● MySQL Installation Displaying variable values Exchanging keys and values ● Apache Installation Writing Your First Script That Multidimensional Arrays ● WAMP Installation Uses Variables Creating multidimensional arrays ● Installing and Configuring PHP Using Variable Variables Viewing multidimensional arrays on Windows. Removing Variables ● How to design PHP applications Using multidimensional arrays in Understanding Data Types statements using Dreamweaver Assigning data types ● How to design PHP -
Lecture 15 Garbage Collection I
Lecture 15 Garbage Collection I. Introduction to GC -- Reference Counting -- Basic Trace-Based GC II. Copying Collectors III. Break Up GC in Time (Incremental) IV. Break Up GC in Space (Partial) Readings: Ch. 7.4 - 7.7.4 Carnegie Mellon M. Lam CS243: Advanced Garbage Collection 1 I. Why Automatic Memory Management? • Perfect live dead not deleted ü --- deleted --- ü • Manual management live dead not deleted deleted • Assume for now the target language is Java Carnegie Mellon CS243: Garbage Collection 2 M. Lam What is Garbage? Carnegie Mellon CS243: Garbage Collection 3 M. Lam When is an Object not Reachable? • Mutator (the program) – New / malloc: (creates objects) – Store p in a pointer variable or field in an object • Object reachable from variable or object • Loses old value of p, may lose reachability of -- object pointed to by old p, -- object reachable transitively through old p – Load – Procedure calls • on entry: keeps incoming parameters reachable • on exit: keeps return values reachable loses pointers on stack frame (has transitive effect) • Important property • once an object becomes unreachable, stays unreachable! Carnegie Mellon CS243: Garbage Collection 4 M. Lam How to Find Unreachable Nodes? Carnegie Mellon CS243: Garbage Collection 5 M. Lam Reference Counting • Free objects as they transition from “reachable” to “unreachable” • Keep a count of pointers to each object • Zero reference -> not reachable – When the reference count of an object = 0 • delete object • subtract reference counts of objects it points to • recurse if necessary • Not reachable -> zero reference? • Cost – overhead for each statement that changes ref. counts Carnegie Mellon CS243: Garbage Collection 6 M. -
VSI Openvms C Language Reference Manual
VSI OpenVMS C Language Reference Manual Document Number: DO-VIBHAA-008 Publication Date: May 2020 This document is the language reference manual for the VSI C language. Revision Update Information: This is a new manual. Operating System and Version: VSI OpenVMS I64 Version 8.4-1H1 VSI OpenVMS Alpha Version 8.4-2L1 Software Version: VSI C Version 7.4-1 for OpenVMS VMS Software, Inc., (VSI) Bolton, Massachusetts, USA C Language Reference Manual Copyright © 2020 VMS Software, Inc. (VSI), Bolton, Massachusetts, USA Legal Notice Confidential computer software. Valid license from VSI required for possession, use or copying. Consistent with FAR 12.211 and 12.212, Commercial Computer Software, Computer Software Documentation, and Technical Data for Commercial Items are licensed to the U.S. Government under vendor's standard commercial license. The information contained herein is subject to change without notice. The only warranties for VSI products and services are set forth in the express warranty statements accompanying such products and services. Nothing herein should be construed as constituting an additional warranty. VSI shall not be liable for technical or editorial errors or omissions contained herein. HPE, HPE Integrity, HPE Alpha, and HPE Proliant are trademarks or registered trademarks of Hewlett Packard Enterprise. Intel, Itanium and IA64 are trademarks or registered trademarks of Intel Corporation or its subsidiaries in the United States and other countries. Java, the coffee cup logo, and all Java based marks are trademarks or registered trademarks of Oracle Corporation in the United States or other countries. Kerberos is a trademark of the Massachusetts Institute of Technology. -
Release 0.11 Todd Gamblin
Spack Documentation Release 0.11 Todd Gamblin Feb 07, 2018 Basics 1 Feature Overview 3 1.1 Simple package installation.......................................3 1.2 Custom versions & configurations....................................3 1.3 Customize dependencies.........................................4 1.4 Non-destructive installs.........................................4 1.5 Packages can peacefully coexist.....................................4 1.6 Creating packages is easy........................................4 2 Getting Started 7 2.1 Prerequisites...............................................7 2.2 Installation................................................7 2.3 Compiler configuration..........................................9 2.4 Vendor-Specific Compiler Configuration................................ 13 2.5 System Packages............................................. 16 2.6 Utilities Configuration.......................................... 18 2.7 GPG Signing............................................... 20 2.8 Spack on Cray.............................................. 21 3 Basic Usage 25 3.1 Listing available packages........................................ 25 3.2 Installing and uninstalling........................................ 42 3.3 Seeing installed packages........................................ 44 3.4 Specs & dependencies.......................................... 46 3.5 Virtual dependencies........................................... 50 3.6 Extensions & Python support...................................... 53 3.7 Filesystem requirements........................................