I am writing a light weight serialization function and need to include two variable sized arrays within this. How should I track the size of each? How should I define the struct? Am I going about this all wrong? EDIT: the result must be a contiguous block of memory ...
I'm looking for something that I presumed would be very simple - given local Unix time in a specific time zone (specified as a string, e.g., "America/New_York" - note that's not my local time), get the corresponding time value in GMT. I.e., something along the lines of time_t get_gmt_time(time_t local_time, const cha...
Say you have the following function: char *getp() { char s[] = "hello"; return s; } Since the function is returning a pointer to a local variable in the function to be used outside, will it cause a memory leak? P.S. I am still learning C so my question may be a bit naive... [Update] So, if say you want to return a new char[]...
I was just playing with the call stack, trying to change the return address of a function etc, and wound up writing this program in C: #include<stdio.h> void trace(int); void func3(int); void func2(int); void func1(int); int main(){ int a = 0xAAAA1111; func1(0xFCFCFC01); return 0; } void func1(int a){ int loc = 0...
Hey guys, I'm working on a commercial project that requires a couple of files to be bundled (packed) into an archive and then compressed. Right now we have zlib in our utility library, but it doesn't look like zlib has the functionality to compress multiple files into one archive. Anyone know of free libraries I'd be able to use for thi...
This might be in vain, as I know writing an operating system is unbearably complicated (especially by oneself). I don't expect to build the next linux, or windows. I know it will be horrible, and buggy, and won't work, but that's fine. I want to write everything myself, in assembly, C, and (some) C++. This is a future project, as I'm...
Is there any study or set of benchmarks showing the performance degradation due to specifying -fno-strict-aliasing in GCC (or equivalent in other compilers)? ...
In C, automatic variables, if uninitialized, hold a garbage value. However, consider the following program: int main(){ signed char term; (char)term--; printf("%d\n",term); } It prints a value of '7'. If I don't do a (char)term--, it prints a value of '8'. So, it definitely doesn't hold a garbage value. Isn't this contradictory? ...
I am especially interested in objects meant to be used from within C, as opposed to implementations of objects that form the core of interpreted languages such as python. ...
what is bitmap in c? ...
Hi, How do I determine if an integer is unassigned? int i; /* no assignment */ if (/* conditional statement here to check if int i is unassigned or not */) { printf("Integer is unassigned!\n"); } else { printf("Integer is assigned!\n"); } Language: C Best regards, Timothy ...
Hi gurus, How to know that fscanf reached a new line \n in a file. I have been using my own functions for doing that. I know I can use fgets and then sscanf for my required pattern. But my requirements are not stable, some times I want to get TAB separated strings, some times new line separated strings and some times some special charac...
I am looking for a good config file library for c that is not xml. Optimally I would really like one that also has python bindings. The best option I have come up with is to use a JSON library in both c and python. What would you recommend, or what method of reading/writing configuration settings do you prefer? ...
I currently have the following code: float a[4] = { 10, 20, 30, 40 }; float b[4] = { 0.1, 0.1, 0.1, 0.1 }; asm volatile("movups (%0), %%xmm0\n\t" "mulps (%1), %%xmm0\n\t" "movups %%xmm0, (%1)" :: "r" (a), "r" (b)); I have first of all a few questions: (1) if i WERE to a...
I have a object store in Java. My C program stores data (in form of char array) in java. Now I wish to retrieve data from my store. I cannot find any function call that returns me an char array. How can I do this? ...
Hi all, I'm trying to call a method from a DLL written in C, from my C# application. Here is how I've implemented the call: --> C method signature: (from a third-part company) Int16 SSEXPORT SS_Initialize(Uint16 ServerIds[], Uint16 ServerQty, const char PTR *Binding, const char PTR *LogPath, Uint16 LogDays, Int16 LogLevel, Uint16 MaxT...
I have a functions which takes a char * as its only argument. I then perform some strtok operations on it. Sometimes it works and sometimes it doesent. It working depends upon how the string was constructed. For instance here are the two cases. int main() { char glob[] = "/abc/def/ghi"; char *glob2 = "/abc/def/ghi"; func(g...
I am using ECPG with PostgreSQL 8.4. I have a function which takes a struct containing pointers to a couple of dynamically allocated, "null"-terminated arrays of integers (I have defined null in this case to be -1, as there is no need for negative values, as in #define INT_ARR_NULL -1 struct foobar { int * foo; int * bar; }; v...
Environment: Win32, C/C++ All three (3) can be used for a thread to signal to main() that it has completed an operation for example. But which one is the fastest signal of all? hmm... ...
What's the best way to declare an integer type which is always 4 byte on any platforms? I don't worry about certain device or old machines which has 16-bit int. ...