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Frame relay basics

Question: Please describe the basic features of frame relay, and how this technology is best used. Answer: Frame relay is a quickly expanding technology that is helping the internetworking industry

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Disconnecting NetWare Users

Question: We have a 250-user NetWare 3.12 installation. How can we effectively terminate inactive workstations? Answer: Here are the parameters that control how long an idle workstation is connected to

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Using strstream for ‘incore’ binary I/O

Question: Can I use strstream functions for incode I/O,i.e. writing to memory just as if it were binaryinput/output to a file? Answer: You can use it to do incode input

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Constructors and virtual functions

Question: I have been doing some programming in C++ and recently decided I would try some Windows programming with the Microsoft Foundation Classes. This isn’t a question about Windows but

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Clearing character arrays

Question: How do you clear a character array? Answer: You can use the standard C library memset function. Here is an example:void foo (){ char t [20]; cin >> t;

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Declaring a bit field for a variable

Question: Is there a way to explicitly declare the number of bits to allocate to a specific variable? For example, can I declare an integer that would be stored in

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Helpful C/C++ newsgroups

Question: Do you know of any good C/C++ mailing lists? I’m a computer science major and I’d like to join one. Answer: I am not aware of any mailing lists

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How portable is C++?

Question: How portable is C++ as a programming language (in terms of different operating systems andhardware)? Answer: C++ is a fairly new language that until recently did not specify anystandard

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Using self-defined libraries

Question: I am using Borland Turbo C++ 3.1 and I can’t figureout how to use my self-defined libraries. I’ve used”#include” but I get an error every time I try touse

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What to do with overload arguments

Question: Which arguments do you receive when you overload . and -> , and what do you do with the arguments? I know that for overloading [] you receive the

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What is pure virtual function?

Question: Can you explain and give me examples of pure virtual function? What is the difference between pure virtual function and virtual function? Answer: A pure virtual function is a

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String tokenizing

Question: I often need to split a string into a number oftokens based on delimiters specifiedby the user. I would appreciate information on how to tokenize a string in a

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Manipulating and using large integers

Question: In several programs, I need to use integers larger than those that can be held by unsigned long ints. I need to be able to multiply, divide, and mod

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File handles/pointers

Question: In C, I use the FILE *filename. As a beginning C++ programmer, I open streams for reading and writing inside the main() function, but when I try to work

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Compilers: Which is best?

Question: Which model of C/C++ compiler offers the best value for a beginning programmer?(It must be ANSI C compatible.) Answer: The GNU G++ compiler. It’s free, ANSI C compatible and

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Possible to read integers as integers?

Question: Is it possible to read integers from a file as integers, or must I read them as strings and then convert them to integers? Answer: In C++ the streams

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Friend class and function

Question: I need to know what the class or function called “friend” is. My teacher explained it in class, but I don’t quite understand how to call it and declare

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Storing strings in a char array

Question: This is actually a simpler form of the real problem I am dealing with. I have a array of char like so:char name[20];Then, I try to put a string

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VC++ 5.0 and STL predicates

Question: How can I provide my own predicate for the list::sort method in Visual C++ 5.0? The method appears to require that any function object passed must be derived from

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Reference Counted Implementation

Question: For a reference counted implementation, how is the operator+= member function coded? The function receives (const String & rhs) and returns String &. The returned String &

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Memory allocation at compile time

Question: Consider the following piece of code:#include /* C++ String class */static String s(“hello”);main() { // … your code s += ” world”; // …}Question: String class uses the new

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Inheritance design

Question: Suppose I’ve got the following class hierarchies:Surface_PlotContourSurface_Plot, child of Surface_PlotSurface_DataGridSurface_Data, child of Surface_DataSurface_Plot contains a Surface_Data object, ContourSurface_Plot contains a GridSurface_Data object.What is the most elegant way to arrange

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Inheritance and parameter pushing

Question: Why do I need private inheritance in C++?Is it true that (in C++) function parameters are pushed onto the stack from right to left? If so, why? Answer: Use

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Compilation Warning

Question: I got a warning when I compiled my C++ program onHP-UX:Line 219: Warning: Namespace is a future reserved keyword (215).What does this mean? Answer: It means exactly what it

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reading input field numbers

Question:   Answer: JavaScript can be used to access values in web form input fields. This is possible because JavaScript treats input fields as objects with several properties. One of

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Persistent Cookies with JavaScript

Question: How can I write a cookie in one page and then read that cookie in another? or alternatively pass data gathered in one page (not a remote!) and then

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undefined vs. null

Question:   Answer: You are probably familiar with a special value in JavaScript called null. This is a value you can assign to a variable when you want to indicate