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

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I'm trying to create a visual representation of something, but I don't know what words to use, so I'll try to describe it

My project team is making a site that will use reddit style voting to track users' opinions on various issues, and use the data to create a "heat map". I say heat map in quotes because I'm not sure ...
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4answers
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main() function prototypes

As far as I know, main () function has the following prototypes: int main(); int main(int argc, char **argv); Now, C does not support overloading, then how are multiple prototypes of ...
5
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1answer
771 views

How much usage of “likely” and “unlikely” macros is too much?

The often known as likely and unlikely macros help the compiler know whether an if is usually going to be entered or skipped. Using it results in some (rather minor) performance improvements. I ...
47
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4answers
28k views

When do you use float and when do you use double

Frequently in my programming experience I need to make a decision whether I should use float or double for my real numbers. Sometimes I go for float, sometimes I go for double, but really this feels ...
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3answers
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Why do programming languages, especially C, use curly braces and not square ones?

The definition of "C-Style language" can practically be simplified down to "uses curly braces ({})." Why do we use that particular character (and why not something more reasonable, like [], which ...
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1answer
203 views

Compile GPL-code into a JNI-capable shared library and use it in commercial software [closed]

I am developing an application for Android in JAVA which calls GPLed C-code via JNI. I have modified & capsulated a GPL-software under a JNI-interface and compile it as a shared library (.so) ...
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1answer
464 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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3answers
278 views

C/C++ in applications that do not concern performance [closed]

C is the best language (or maybe the single language) suitable for operating systems, drivers, embedded systems etc. For more complex domains like computer graphics C++ is a better choice. But these ...
8
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1answer
9k views

programming PID loops in C

I'm an electrical engineer that was kind of thrust into the digital world and learning as I go. I'm programming a TI processor to do a PID (proportional-integral-derivative) loop, illustrated by this ...
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7answers
3k views

When should pointers be checked for NULL in C?

Summary: Should a function in C always check to make sure it is not dereferencing a NULL pointer? If not when is it appropriate to skip these checks? Details: I've been reading some books about ...
1
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1answer
286 views

Portability: Python's C/C++ libraries/extensions vs JRuby's Java libraries

I've had some discussion with colleagues who chose to go with JRuby along the following line of argumentation: JRuby can make use of anything that is available in Java, ergo such programs are more ...
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2answers
261 views

Need some advice and feedback on my code's design

I am looking for feedback on the design of my program. I have a shell script call function.sh that defines a lot of helper functions. My intent is to use those bash functions defined in functions.sh ...
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2answers
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What is the purpose of NaN boxing?

Reading 21st Century C I arrived at chapter 6 at the section "Marking Exceptional Numeric Values with NaNs", where it explains the use of the bits in the mantissa to store some arbitrary bit patterns, ...
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2answers
1k views

Library design: provide a common header file or multiple headers

There are essentially two camps of library designers concerning the design of the final header file inclusion: Provide a single header file that includes every other header file that makes up the ...
1
vote
1answer
157 views

Implementing a sort of navigation system

So I am undertaking a project which does navigation sort of thing. So here is how the problem statement looks like. Say, given a map of a floor, with different rooms, now somehow, this information is ...
2
votes
1answer
407 views

Where did the T in wchar_t come from?

In many native types, a common suffix (and sometimes prefix) of t or _t is used to denote platform-independent types (such as wchar_t, int32_t, etc.) What was the logic behind the letter t as opposed ...
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2answers
838 views

Why aren't there modern C IDEs? [closed]

Why weren't the features present in modern IDEs for Java & C# (Intellij IDEA, Visual Studio, eclipse) developed in (earlier) IDEs for C language? I mean I don't know any IDE which has modern ...
4
votes
4answers
35k views

Initializing char array with string

I don't remember how I got to the thread, but I was reading its replies and one of them states that you should never initialize a char[] with a string literal. My question: Is initializing a ...
1
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1answer
507 views

Parallel computing using xcode

I'm making mandelbrot fractals in C using Xcode and I want to use parallel computing but everything I've tried so far doesn't work. Such as This Question and other how to guides. Whats the easiest way ...
4
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2answers
5k views

Low Latency Unix/Linux

Most low latency/high frequency programming jobs (based on job specs) appear to be implemented on unix platforms. In a lot of the specs they make particular request for people with "low latency linux" ...
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2answers
489 views

How to practice programming? [closed]

I've been a PHP developer for 5 years now. Before I started working in that field, I've been practicing at home. I've created my own CMS, so I could actually show some of my code to the potential ...
7
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5answers
985 views

Is code duplication a necessary evil in C?

I'm rather new to C, and I'm wondering if code duplication is a necessary evil when it comes to writing common data structures and C in general? I could try to write a generic implementation for a ...
21
votes
2answers
1k views

What does it mean to expose a C++ code publicly as a C API and what are the advantages of doing it?

I often hear people say that C++ programmers should expose their library's/product's public API as a C API. What does that mean and what are the advantages of that?
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1answer
2k views

Streaming data from a microcontroller to a server? [closed]

Edit *We have a heart monitor hooked up to to an msp430 with a roving networks wifi module. I would like to connect send some type of a datastream to a webserver so that someone could watch it ...
3
votes
6answers
6k views

What is a 'Null Terminated String' ?

I have just started reading C++, and I came across a term "Null Terminated String", I read about it but couldn't understand what it actually stands for. I also want to know what is the difference ...
6
votes
1answer
272 views

Difference between language virtual machine and emulating vm?

I'm having a hard time understanding the difference between an emulation virtual machine and a language vm. I started with the research and implementation of an emulation virtual machine. Primarily ...
4
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2answers
292 views

What is the lifecycle for loading a Linux Desktop Environment?

I'm looking into delving into a bit of custom OS work (and yes I understand that doing any development at the DE level or lower on an OS is extremely complex and not a light thing to undertake, ...
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3answers
768 views

How to efficiently store IP addresses? [closed]

Background I have a requirement where I need to remove a few nodes in a network based upon a command given by the user. To keep the nodes from transmitting or receiving data I thought of changing its ...
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8answers
1k views

Does low latency code sometimes have to be “ugly”?

(This is mainly aimed at those who have specific knowledge of low latency systems, to avoid people just answering with unsubstantiated opinions). Do you feel there is a trade-off between writing ...
3
votes
3answers
288 views

is Microsoft LC random generator patented?

I need a very simple pseudo random generator (no any specific quality requirements) and I found Microsoft's variant of LCG algorithm used for rand() C runtime library function fit my needs (gcc's one ...
4
votes
1answer
232 views

unseen/unknown function definition in linux source

Can any one please explain this piece of code I found in the linux kernel source. I see a lots of code like this in linux and minix kernel but dont seem to find what it does (even if C compilers ...
2
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8answers
775 views

tips, guidelines, points to remember for rendering professional code? [closed]

I'm talking about giving clients professional looking code. The whole nine yards, everything you hardcore professional highly experienced programmers here probably do when coding freelance or for the ...
15
votes
8answers
2k views

Why does Clang/LLVM warn me about using default in a switch statement where all enumerated cases are covered?

Consider the following enum and switch statement: typedef enum { MaskValueUno, MaskValueDos } testingMask; void myFunction(testingMask theMask) { switch theMask { case ...
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3answers
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Which language is more suitable heavy file tasks?

I need to write a script (based on basic functions) to process /image/audio/video files. The process is mainly filesystem tasks and converts. The database of files has been stored by mysql. The script ...
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2answers
491 views

What are the ways to start making actual/real-world programs using Java/C++ to excel my Programming Skills? [duplicate]

Possible Duplicate: How do I improve my coding skills? How I do become a better programmer as a junior developer The programming that we learn at university is not that vast, like those ...
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13answers
4k views

Why do operating systems do low level stuff in C and C++? Why not just C++?

On the Wikipedia page for Windows, it states the Windows is written in Assembly for the bootloader and task switcher, and C and C++ for kernel routines. IIRC, you can call C++ functions from an ...
4
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2answers
778 views

How can I combine C/Fortran with JavaScript?

I'm working on a project where I need heavy numerical calculations to be real-time visualized with something flexible like D3.js. Are there frameworks out there that would let me painlessly achieve ...
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3answers
251 views

Random List of numbers in C

I have just started a C programming course and so far have only done the basics like printf, read a little on variables etc on the course book. The teacher has tasked us with writing a program that ...
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1answer
237 views

C Minishell Command Expansion Printing Gibberish

I'm writing a unix minishell in C, and am at the point where I'm adding command expansion. What I mean by this is that I can nest commands in other commands, for example: $> echo hello $(echo ...
6
votes
2answers
392 views

Are there any reliable solutions for annotations/reflection/code-metadata in C?

Not all languages support java-like annotations or C#-like attributes or code metadata in general, however that doesn't mean it is not possible to have in languages that don't have this. An example ...
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4answers
853 views

C simple arrays and pointers question

So here's the confusion, let's say I declare an array of characters char name[3] = "Sam"; and then I declare another array but this time using pointers char * name = "Sam"; What's the ...
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votes
3answers
959 views

Why does an unsigned int compared with a signed character turn out with an unexpected result? [closed]

Why does the following code output y>x when clearly 1>-1? unsigned x=1; signed char y=-1; if(x>y){ printf("x>y"); } else { printf("y>x"); } Please explain this result.
2
votes
1answer
301 views

Brief explanation for executables in a GNU/Clang Toolchain?

I roughly understand that cc, ld and other parts are called in a certain sequence according to schemes like Makefiles etc. Some of those commands are used to generate those configs and Makefiles. And ...
2
votes
4answers
1k views

Should I use C style in C++?

As I've been developing my position on how software should be developed at the company I work for, I've come to a certain conclusion that I'm not entirely sure of. It seems to me that if you are ...
0
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2answers
305 views

How to access an encrypted INI file from C on an embedded system with little RAM

I want to encrypt an INI file using a Delphi program on a Windows PC. Then I need to decrypt & access it in C on an embedded system with little RAM. I will do that once & fetch all info; I ...
8
votes
4answers
2k views

Is it important to know C/C++ for Android development?

Is it possible to use only Java (without C++ /NDK) for building good, fast, beautiful Android apps (including 3D development)? When I look for Android developer position requirements (vacancies), I ...
1
vote
1answer
58 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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4answers
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Is there any difference between return n and exit(n) in C?

Is there any difference between return n (in the main function) and exit(n) in C? Is it defined by C or POSIX standards or it depends on OS or compiler?
6
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3answers
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Approach for developing software that will need to be ported to multiple mobile platforms in the future

I am currently doing the preliminary design for a new product my company will be pushing out soon. We will start on Android, but then we will need to quickly develop the IPhone, IPad.... and then the ...
3
votes
1answer
2k views

Optimal buffer size for fread/fwrite [closed]

What buffer size should I choose for read/write files via POSIX fread/fwrite functions?