c

Answer difference in C

Possible Duplicate: Could anyone explain these undefined behaviors (i = i++ + ++i , i = i++, etc) int a=2,b=3,c; c=a++ + a-- + b++ + b--; printf("%d",c); and int a=2,b=3; int c=a++ + a-- + b++ + b--; printf("%d",c); in first case ans comes 10 but in second case ans comes 12 why? ...

How do I find the current system timezone?

On Linux, I need to find the currently configured timezone as an Olsen location. I want my (C or C++) code to be portable to as many Linux systems as possible. For example. I live in London, so my current Olsen location is "Europe/London". I'm not interested in timezone IDs like "BST", "EST" or whatever. Debian and Ubuntu have a file /...

Linux / C Check if a char contains spaces, the newline character or the tab character

I have a GtkEntry where the user has to enter an IP number or a hostname. When the button is pressed what the user typed into the entry is added to a char. How can I programmatically check if this char contains spaces, the newline character or the tab character? I don't need to remove them, just to know if they exist. Thanks in advance! ...

Building a project with CMake including other libraries which uses different build systems

I am working on an open source project which uses C for libraries, C++ for GUI and Cmake for managing build. This project is just started and have only couple of files. I can successfully generate makefiles on my linux development environment and on windows I can generate Visual Studio project files using CMake. All works well so far. A...

C attempt to difference a generic pointer

Hello, I try to call g_io_scheduler_push_job(job_func, &param, NULL, G_PRIORITY_HIGH, generator_cancellable); In my C/gtk+ application for runing job_func in another thread then main program. But have segfault when i call this function, and debugger sad that: ** userdata attempt to difference a generic pointer** My job_func: gbool...

Where are the C header files in Windows?

I'm new to Windows development, having messed around in Linux for a while. I need to access console functions and am having trouble getting a comprehensive list of console text attributes off the web. I would like to read wincon.h and windows.h to get the info, but I can't figure out how to get at them. Help please! ...

Creating an OS close button? (WinAPI)

I want to create a button that is basically Windows' close button. How could I do this? I want to avoid drawing this myself because I want it to look like that version of Windows' close button. Firefox's tabs do something like this. Thanks ...

How to concatenate 2 or more Integers using Macros?

If a=1, b=2, c=3... i would like to write a macro which concatenates them like this 123. But when i try this: #include<stdio.h> #define cat(a,b,c) a##b##c int main() { int a=1,b=2,c=3,d; d=cat(1,2,3); //Works d=cat(a,b,c); // Returns an error...How to make this work? return 0; } ...

Document an IDL-generated C API with Doxygen

Hi, My company develops a primarily C-based API, using IDLs to define the interfaces and generate the C headers. We'd like to use Doxygen to document the interfaces in the IDLs, but we'd also like the API reference to document the C headers. In other words, the fact that we are using IDLs should be transparent to the customers of our ...

Configure Doxygen to hide certain names or keywords

I'm just getting started with Doxygen, and have done considerable searching on this, so forgive me if there's an obvious answer. I'm working on an embedded project where functions can be tagged as debug or nodebug before the return type. In most of our libraries, we use a conditional macro to set libname_debug to either debug or nodebu...

Documenting macros (with doxygen) for a member of a struct

I prefer to define certain macros inside of my struct definitions, so it's easy to see possible values for a given member. For example: typedef struct foo_t { uint16_t flags; #define FOO_FLAG_BELL 0x0001 #define FOO_FLAG_BOOK 0x0002 #define FOO_FLAG_CANDLE 0x0004 #define FOO_FLAG_LANT...

Is a C .lib file platform specific?

I'm trying to use an API for a proprietary interface device on an embedded system (Freescale HCS08), and the provided files include headers (.h) and libraries (.lib). The header compiles fine with the rest of my code (standard C), but when trying to link against the library I get memory errors saying the file might be corrupted. My und...

Operator Precedence in C

Possible Duplicate: Could anyone explain these undefined behaviors (i = i++ + ++i , i = i++, etc) Hi, if x = 10, y=11 then, can anyone please explain why int temp = x++ + ++y + x++; then, temp has a value: 33 but x = x++ + ++y + x++; then, x has value: 34 and when x = ++x + ++y + x++ then, x has value: 35 Com...

Makefile: Efficient way to make all '.c' files depend on a header file with the same name?

I have a directory with 50 .c source files and each one of these .c files depends on a .h file with the same name plus a common header file. Example: foo.c depends on foo.h and common.h bar.c depends on bar.h and common.h baz.c depends on baz.h and common.h Is it possible to setup this dependency without having to make a separate tar...

get strings from the buffer

Hi, I wish to get strings from the buffer of raw bytes in the memory, will work well? static int in = 0; void *loadFile (FILE *fp) { fseek (fp, 0L, SEEK_END); size_t size = ftell (fp); fseek (fp, 0L, SEEK_SET); char *buf = malloc (sizeof(char) * size); if (!buf) return NULL; if (fread (buf, sizeof...

Better practice to strcpy() or point to another data structure?

Because it's always easier to see code... My parser fills this object: typedef struct pair { char* elementName; char* elementValue; } pair; My interpreter wants to read that object and fill this one: typedef struct thing { char* label; } thing; Should I do this: thing.label = pair.elementName; or this: thing.label = (char*)...

Scientific Library Options for C or C++

I'm in the process of choosing a scientific library to use as a basis for a project. I need to do a lot of statistical, linear algebra, and signal processing tasks, and I figured there are probably some great libraries that already do this stuff better than I could program it myself. For c++, I know about Boost, but don't have much expe...

Using of deeply nested pointers

Suppose we have to use in some function deeply nested pointer very extensively: function (ptr_a_t ptr_a) { ... a = ptr_a->ptr_b->ptr_c->val; b = ptr_a->ptr_b->ptr_c->val; ... } Assuming all pointers are checked and valid, is there performance degradation, problems with atomicity or other caveats (except readability) in...

Is there a function like asctime_s() that works for SYSTEMTIME structures in windows?

I know I can do this if I have a struct tm structure, but what if I want to do the same thing with a SYSTEMTIME. I could do this manually but just wondering if there's function that does this already. Thanks void PrintTimeSCII(struct tm *time) { char timebuf[26] = {0}; asctime_s(timebuf, 26, time); printf("%s\n", time...

How can I randomize a sequence of characters?

I want to write a function which randomizes the order of a sequence of alphabetic characters. For example, the sequence: A B C D E F G . . . ...might be changed to: Z L T A P ... ...which, if passed to the same function again could result in: H R E I C .... Any suggestions? ...