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

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6
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3answers
377 views

How to extract the active code path from a complex algorithm

I have been puzzled lately by an intruiging idea. I wonder if there is a (known) method to extract the executed source code from a large complex algorithm. I will try to elaborate this question: ...
2
votes
2answers
540 views

Is there a better way to organize my module tests that avoids an explosion of new source files?

I've got a neat (so I thought) way of having each of my modules produce a unit-test executable if compiled with the -DTESTMODULE flag. This flag guards a main() function that can access all static ...
1
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2answers
106 views

Complex iterators in C

note: this was originally asked on SO. Part of my current project involves iterating over sequences that don't necessarily exist. For example, I have something similar to a relational database in ...
2
votes
0answers
170 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 ...
2
votes
0answers
407 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 ...
1
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0answers
171 views
+100

Fast fixed-size (256 bit) integer modulo/division

What is the fastest way to divide two 256-bit integers? They are represented as an array of 26-bit words, each stored in 32-bit integers. I have access to a 64-bit type if that's useful. It seems ...
1
vote
0answers
87 views

How to use an enumeration type, when the values are not known at first?

We have a project, that consists of a cluster of C source code, a C library and a C++ library. The C++ library is dependent only upon the C library, or at least that is what I am trying to achieve. ...
1
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0answers
65 views

type name for state machine state (as opposed to other state variables)

I need to create a typedef for a state machine state, e.g. enum ToasterStateMachineState { TSM_READY, TSM_TOASTING, TSM_DONE }; But ToasterStateMachineState seems verbose and redundant; is ...
1
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0answers
335 views

How does a dynamic library's references to a static variable get translated once in the running app?

If a dynamic library exports the address to a global variable defined within the library, how are accesses to that variable translated during dynamic linking so that a running application can interact ...
0
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0answers
42 views

inserting into priority queue. MIT c programming opencourseware

Iam currently trying an exercise from the "practical programming in C" from MIT opencourseware. the exercise is on huffman coding. it is lab2 part 2 where Iam having an Issue. Primarily the ...
0
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0answers
41 views

A callback for when data is received?

So, my understanding is that the Kernel could receive TCP at any time, and that generally a C program asks the Kernel synchronously/asynchronously if it has data available. Would it be possible for a ...
0
votes
0answers
29 views

Synchronizing content between web-based app and game server

I have a MUD server, written in C, that I'm trying to move from file-based storage to MongoDB. Eventually, I'd like to offload administration of game content and settings to a web console, written in ...
0
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0answers
63 views

GMP Core Dump while using mpz_clear in C

I'm working on a prime factorization program written in C using the GMP library through cygwin. The algorithm that I have now works fine, but has memory leaks from not using the mpz_clear function on ...
0
votes
0answers
87 views

Best way to signal all child processes to terminate using C

I have been assigned the task of designing a simple web server using C in my UNIX & C class. The webserver listens and forks when a successful connection is made so that multiple clients may be ...
0
votes
0answers
74 views

Abstract Web API from validation and configuration management in embedded system

Im working with embedded Linux for a router. There is a web GUI for the user to configure router options. When user fill a web form this is submitted to a web server function that is responsible of ...
0
votes
0answers
131 views

Writing Z80 table based assembler/disassembler

I have a long-term project: DIY computer with various processors. One of my wishes not only make hardware, but software too. So I started from assembler/disassembler for Linux, though there is a lot ...
0
votes
0answers
72 views

Does multiple Bloom filters make sense?

In order to decrease the number of false positives, I came up with a couple of possible solutions. Create two different types of Bloom filters; eg. filter1 using 3 different hash algorithms, filter2 ...
0
votes
0answers
203 views

In-place merging of sorted intervals in an array?

So I have code producing k sorted intervals in an n-sized array. What I'm brainstorming is the possibility of in-place merge of these intervals into a single sorted interval/array. The problem is ...