C is a general-purpose computer programming language used for operating systems, games and other high performance work.

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Maintaining code-style conventions for large projects [closed]

For a while I've been maintaining an ad-hoc script to check code style against our project's guidelines. I'm aware of AStyle/Uncrustify and have used them, but they are best for once-off code-style ...
2
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1answer
84 views

In GSL, why do some functions take a “workspace” argument?

In certain functions in GSL (GNU Scientific Library), some functions take a "workspace" environment as an argument. For example, gsl_poly_dd_taylor from this page. Why? Wouldn't it be easier for ...
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1answer
232 views

Setting source IP with posix sockets

Is it possible for an application to request a socket (tcp) and have it set the source address without using raw sockets? (the addresses would be bound to the interfaces. [no spoofing]). This would be ...
2
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1answer
227 views

How to run thread if multiple data is insert in the multiple table

I'm facing problem in gsoap , if two user go to register at a same time then database is locked, i think its threading problem , how to handle it, please insist me. I am running multiple ...
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2answers
528 views

Communication between state machines with hidden transitions

The question emerged for me in embedded programming but I think it can be applied to quite a number of general networking situations e.g. when a communication partner fails. Assume we have an ...
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5answers
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Correct For Loop Design

What is the correct design for a for loop? Felix currently uses if len a > 0 do for var i in 0 upto len a - 1 do println a.[i]; done done which is inclusive of the upper bound. This ...
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1answer
185 views

Can anyone recommend a toolchain-agnostic way of declaring and documenting inter-package build dependencies?

I currently have a project at my hand that I'll leave soon (PhD work) and should be left in an understandable form since it is likely to be taken up, though it is not known yet by whom and when. ...
2
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1answer
426 views

How do you handle multiple projects that form the same product(s)?

I have limited experience when it comes to build and version control systems. I feel like I've run into a common problem but I'm having trouble uncovering how it is typically handled. Say you have ...
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2answers
386 views

Best practice for shared files within multiple unit test fixtures

I was wondering what the general best practice is for when you have multiple unit test fixtures testing different things that use the same file paths. My test files are in a directory tree with ...
2
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1answer
84 views

Questions about compiler/interpreter design [closed]

I am implementing a programming language, for fun, in C. I have most of the parsing code done and also the AST ready. I once did write a runtime for this language some time ago, but I had some trouble ...
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1answer
151 views

Using own ArrayList in general purpose C libraries, but allowing a different implementation

I've written a couple of libraries since beginning to use C again last year. One thing that still needs addressing in both of these is the correct use of array-based lists - hereafter, ArrayLists. At ...
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198 views

Have any C compilers ever *defined* `unsigned short x=-3; x*=x;` to yield anything other than 9

In a C implementation where int can hold all values of type unsigned short, standard integer promotion rules dictate that given the code: unsigned short x=(USHORT_MAX+1)-3; // Or just -3 x*=x; a ...
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545 views

using flat file vs sqlite db for frequent data grabbing in a cron job

I have some automated task to be done using certain types of logs generated on the server end of each day. Log files contains specific machine identification "MAC" that is to be re-written in to ...
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4answers
678 views

Why C language is taught as the basis of Computer Programming Languages? [duplicate]

I often wondered why C Language is taught as the basis of programming languages everywhere. There are a lot of modern languages like Java, Python etc. which makes the syntax and programming easier. ...
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5answers
1k views

How to learn C in two days (if I already know C++)? [closed]

I've been programming in C++ for a few years, and I've done a school project or two in C (as well as several other languages). However, I don't know C very well at all. I have a programming ...
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1answer
665 views

Using assembly to write to a file

I am working with a trading application (reading data from the exchange) which generates a bucket load of data on a per second basis. We have different "log-levels" but even the minimal log-level ...
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4answers
926 views

Indenting labels in C

I noticed that in the Vim automatically indents labels in a rather unintuitive way (IMHO). int main(void) { goto end; end: return 0 } Are there any style guidelines for labels? For the ...
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8answers
1k views

Is C a MUST-learn language for programmer? [duplicate]

Possible Duplicate: I don't know C. And why should I learn it? I start my programming from Java, and learned PHP. Also, because of the work, I learned Objective-C. But most of the ...
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3answers
592 views

Objects in non-OOP languages

Can we use the word "object" for data / functions in e.g. C (or Pascal) which doesn't really have objects? In C, what is an object? A data structure? A named memory area? I spoke to my collegue about ...
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4answers
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How do I refer to the smallest possible non-zero value?

Back in my C programming days I thought there was a constant or function (I can't remember what it was called, let's call it SMALL) whose value was the smallest possible positive value. (Imagine the ...
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5answers
4k views

How to share memory between applications written in C/C++

I'm going through a program written in C/C++ for control in robotics. Basically, three different programs run at the same time, and they communicate via shared memory. Google-ling around I found ...
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3answers
431 views

Alternative to goto-statement in this case? [duplicate]

Currently I am using gotos for closing handles and general cleanup if an error occurs. Since I don't want to nest all the ifs and a function for cleanup would require a return besides the cleanup(); ...
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2answers
6k views

How do we go from assembly to machine code(code generation) [closed]

I know this is abstract as it's all about signals and switch - (electronics) - underneath, but is there a easy way to visualize the step between assembling code to machine code. For example if you ...
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3answers
452 views

C: “this” vs “<instance name>”

I'm using C in a minimal, efficient OOP style to build a game engine. A problem I've begun to face as the engine code settles is my (erstwhile) choice to use this. For example, I have: void ...
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2answers
775 views

Searching algorithm used in switch statement

What is the searching algorithm used in switch statement in C language? If the cases are not in order still it searches proper case which means it is not a binary search algorithm, can anybody ...
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372 views

Why is it called a memory leak?

I am a hobbyist programmer, bit of a stickler for terminology, currently learning C and recently came across the concept of Memory Leak. Now, I do understand what it means. Dynamic memory allocated to ...
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2answers
306 views

Creation of an Assembler [closed]

I've always been interested in how programming languages are created, so for the past 8 months I've been researching, practicing and more about the creation of compilers. I've been able to quite ...
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3answers
121 views

Application that provides unique keys to multiple processes

Any idea on how to build an application that provides unique keys each time it get called by another process. Calling process isn't my problem here, my problem is how to sync between two(or more) ...
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2answers
4k views

Assigning strings to pointer in C

My question is about pointers in C. As far as I've learned and searched, pointers can only store addresses of other variables, but cannot store the actual values (like integers or characters). But in ...
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3answers
489 views

How do you read this line of code?

Forgive me for my poor English, me and my friend were doing school homework, suddenly he asked me to read this line of code ptr = &array[1][1][1] (ptr is a pointer to an integer). He said ...
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1answer
417 views

How is this number calculated?

I have numbers; A == 0x20000000 B == 18 C == (B/10) D == 0x20000004 == (A + C) A and D are in hex, but I'm not sure what the assumed numeric bases of the others are (although I'd assume base 10 ...
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3answers
2k views

How should I implement a secure priority queue in C?

I have an assignment to implement a priority queue in C as well as make an app that uses it. I, however, only know basic-level C (I do know Java). My intuition says that I need to learn pointers. ...
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3answers
150 views

Comparing multiple revisions of the same C File

I just wondered if anyone had any tricks or programs they used when comparing two of the same file but different versions? I appear to have foolishly made a modification at some point today (Went a ...
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2answers
378 views

“bug” in C++11 text by Stroustrup?

I found an apparent contradiction in the c++ text having to do with the result of the c_str() function operating on std:strings (in my copy, the definition and contradiction are on p1040). First it ...
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2answers
564 views

Multiple Data Types for Single Variable in C

I am trying to implement basic cons, car and cdr of SCHEME in C. I have made a simple program that allows me to cons two integers as shown in the main program. However, I want my program to be able to ...
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2answers
121 views

Declaration confusion in pointers [closed]

I was just confused about the following declaration in C: char **p[5] I understand the char *p[] as an array of character pointers, but this one is puzzling me. Based on the precedence of [] over ...
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1answer
217 views

How to represent “class” data type in C or any low level language? [closed]

I'm writing a simple language compiler,currently it's support functional programming only. I want to support OOP concept, but I don't know how exactly I can represent an object ? just where to start ...
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5answers
142 views

Does it make sense to have a separate init function?

I'm created an opaque type and I have two options for its management. The first looks like this: type_t *a = type_init(); int err; err = type_do(a, "foo", "bar", FLAGBIT1|FLAGBIT2, NULL); if (!err) ...
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4answers
211 views

What should I do and know before I start writing C? [closed]

I have a college degree in CS, and learned about Java and OCaml. Java was used as introduction, and in most CS classed, except the theoretical ones. OCaml was part of learning a different programming ...
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2answers
6k views

When using int's as boolean values, is it in poor form to use 0's and 1' directly?

Is it better to do this #define INT_TRUE 1 #define INT_FALSE 0 int someFunctionalityIsEnabled = INT_TRUE; or this? int someFunctionalityIsEnabled = 1; It can be safely assumed that false will ...
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3answers
127 views

How much can you detect undefined behaviour using testing [closed]

I hope this question fits this site. You may know you can't detect undefined behaviour in C using compilers - and some tools (static analysis) can help you detect it. My question is more empirical - I ...
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2answers
1k views

Which is better: for valid buffer length?

This is a basic question. But, I think understanding this would be helpful to play with buffers in 'C'. Thanks. Scenario Just a sample snippet char *test_buff = (char *) malloc(512); //allocate 512 ...
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3answers
198 views

Requiring a specific order of compilaiton

When designing a compiled programming language, is it a bad idea to require a specific order of compilation of separate units, according to their dependencies? To illustrate what I mean, consider C. ...
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2answers
449 views

Python as a first language? [closed]

I have just started working in Information Security World. I want to learn the Python language for creating my own automated tool for Fuzzing, SQL-Injection etc. My question is I don't know much ...
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1answer
527 views

Help me construct a list of best approaches for new C and C++ developers [closed]

Not specific code writing practices. Please also include reasoning. My start: use GCC or Clang gcc because it is unchallenged in the amount of static checking it can do (both against standards ...
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2answers
115 views

Multi-pattern matching

I have a given byte array in C and I need to match it against several byte arrays and return true if there is any match. I can make various memcmp's but I feel that it is very inefficient. Do you ...
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1answer
182 views

What is this boolean law?

A friend of mine has shown sometime ago the name of the below boolean technique/law but I forget that name unfortunately. Does someone know what it's called? example in C language: !(a || b) It's ...
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566 views

GPLv2 - Multiple AI chess engines to bypass GPL

I have gone through a number of GPL-related questions, the most recent being this one: http://stackoverflow.com/questions/3248823/legal-question-about-the-gpl-license-net-dlls/3249001#3249001 I'm ...
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3answers
437 views

What does the “t” in int32_t signify?

In C, what meaning, if any does the t at the end of integer types like uint8_t and int32_t have? Where did it originate? Why wasn't the type just called int32?
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2answers
149 views

How much does C help you in other languages? [duplicate]

How much does learning C to moderate level help you as a programmer. For example, does being competent in C make it easier to pick up languages as time goes on and get a better understanding of them?