c

Replace placeholders with text - C ?

I use the below function to retrieve characters one by one from a FILE stream. Now the text in that file will sometimes include places holders like !first_name! within the text. What's the best way to detect when such a place holder start and when it ends so that I can swap each character between !! with proper character from another sto...

Converting between C++ std::vector and C array without copying

I would like to be able to convert between std::vector and its underlying C array int* without explicitly copying the data. Does std::vector provide access to the underlying C array? I am looking for something like this vector<int> v (4,100) int* pv = v.c_array(); EDIT: Also, is it possible to do the converse, i.e. how would I ini...

strlen() implementation in gcc

Can anyone point me to the definition of strlen() in GCC? I've been grepping release 4.4.2 for about a half hour now (while Googling like crazy) and I can't seem to find where strlen() is actually implemented. ...

Where can I get C/C++ sample code for merge sort a link list?

Where can I get a sample code for merge sort a link list? ...

What is the best way to sort link list?

What is the best algorithm to sort a link list [in C/C++]? ...

Unit testing real-time / concurrent software

The classical unit testing is basically just putting x in and expecting y out, and automating that process. So it's good for testing anything that doesn't involve time. But then, most of the nontrivial bugs I've come across have had something to do with timing. Threads corrupt each others' data, or cause deadlocks. Nondeterministic behav...

excellent setjmp/longjmp tutorials

Hi I'd like to read good tutorials on setjmp/longjmp in C. It'd be better if there're examples which are real rather than artificial. Thanks. ...

C: Correctly freeing memory of a multi-dimensional array

Say you have the following ANSI C code that initializes a multi-dimensional array : int main() { int i, m = 5, n = 20; int **a = malloc(m * sizeof(int *)); //Initialize the arrays for (i = 0; i < m; i++) { a[i]=malloc(n * sizeof(int)); } //...do something with arrays //How do I fre...

What are often used network programming functions/code snippets?

All of us who still do some kind of network programming (TCP/UDP, DNS or Client/Server) in C repeatedly use some code snippets again and again. We do use some standard libraries but then also we do write some code very often which is not there in one library. Is there a collection of such code snippets that are used very often. If no...

In C how do I print filename of file that is redirected as input in shell

$cc a.c $./a.out < inpfilename I want to print inpfilename on stdout. How do I do that ? Thanks for the help in advance... ...

Name of C/C++ stdlib naming convention?

I wonder if the naming convention used in C/C++ standard libraries has a name, or at least a cheat-sheet where I can lookup the rules. E.g. push_back -- underscore used setstate -- but not used here! string::npos -- when to use abbreviations? fprintf ... Does the naming convention used in the C/C++ standard libraries have a sp...

Hashes in Cocoa and Objective-C

Hi, I'm writing an application for Mac. I need some code which generates a hash from a string. I need to create these hashes: MD2 MD4 MD5 SHA-0 SHA-1 How can I do this? Thanks. ...

emacs C and C++

Hi there, I have some very specific questions related to emacs for building C applications: 1) How can I compile a file written in C/C++ using emacs. 2) How can I have something similar with MS Intellisense in emacs? 3) How can I add an C/C++ library to the compiler and emacs to know about it. many thanks ...

Passing an argument on libpcap pcap_loop() callback

Hi, Because I would like to make some tests with the libpcap and a small C program, I am trying to pass a structure from main() to got_packet(). After reading the libpcap tutorial, I had found this: The prototype for pcap_loop() is below: int pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user) The last argume...

URL regex with regex.h in c

SO: I'm having a bit of difficulty setting up a regex to match a URL using the regex.h library in c. I have a working IP regex that I was hoping to convert to match a simple string such as www.alphanumerictext12.com|edu|org. Something is wrong with my syntax in the regex definition itself. Below is the working IPREGEX code and my a...

Basic HTTP firewall

I am beginning work on an intelligent firewall but before I do that I need to understand clearly how a very basic firewall will work. Since me and my team is most comfortable in C we are going to use that. Could someone give example of a very basic firewall written in C. ...

HTTP proxy server

I am beginning work on a very basic HTTP proxy server written in C (Edit: something that just forwards my requests). At this point I am having difficulty in understanding how to proceed. Any help would be beneficial. ...

Read a file into dynamic memory array using malloc and POSIX file operations

Possible Duplicate: reading a text file into an array in c Hi, I'm trying to read a file into a dynamic array. Firstly I open the file using open() so I get the file descriptor But then I don't know how can I allocate the memory using malloc to a dynamic array in order to do some data modification in the file from memory. Than...

eclipse with php and C/C++

hi there I'm into the learning stage of C and PHP. Until now I was using MS Visual Studio IDE for C/C++ applications and Notepad++ for PHP application. Now I'm thinking to use same IDE for those languages and Eclipse seems to support both of them. My questions are: - Do you think is good to forgot about using MS Visual Studio for Ecl...

How/Why is imagedata stored as char - OpenCV

I'm a tad confused. I am just getting started with OpenCV and its image data is pointed to by a char pointer. I can't quite work out how that works considering the actual data itself could be any number of data types, e.g. uint, float, double. As far as I knew, a pointer had to be of the same type as the pointer it represents. It's p...