Hello guys, Recently an interviewer asked me about the types of buffers. What types of buffers are there ? Actually this question came up when I said I will be writing all the system calls to a log file to monitor the system. He said it will be slow to write each and every call to a file. How to prevent it. I said I will use a buffer an...
OK, so I don't sound like an idiot I'm going to state the problem/requirements more explicitly: Needle (pattern) and haystack (text to search) are both C-style null-terminated strings. No length information is provided; if needed, it must be computed. Function should return a pointer to the first match, or NULL if no match is found. Fa...
Hi, I tried loading C shared library .so in Python using ctypes.CDLL class (Linux). Here is the link to which tells what I did. As I see the documentation it says CDLL class assumes that function returns int types. I've a doubt here what if I need to return variable of type other than the int type from a function in C?. And to what exte...
I am having a total mind blank on this at the moment. I have a cube (voxel) that is defined by a centre point and a width, height and depth of 1. If I have a vector with an origin from the centre of the box (E.g. (-0.7,-0.7, -0.7)) how do I calculate the point at which the vector intersects the outside of the box? EDIT: The box is alwa...
I want to use the git's malloc and realloc wrappers in my code for OOM(out of memory) conditions. Here is its code: void *xmalloc(size_t size) { void *ret = malloc(size); if (!ret && !size) ret = malloc(1); if (!ret) { release_pack_memory(size, -1); ret = malloc(size); ...
I'm searching a fast (specially the p^n mod g operation, should be implemented with montgomery) big integer library. I know there is GMP but GMP is LGPL which doesn't fit my requirements. I tried http://www.acme.com/software/bigint/ and tried to optimize the modpow in there. But do to the fact that the data is stored with base 2^32 it i...
I want to extract every audio channel in a quicktime movie with the QuickTime-API. That means if the file has 5.1 surround, i want 6 audio files in the end. But at the moment I don't know how to manage that. Until now I have: OSStatus err = noErr; MovieAudioExtractionRef extractionSessionRef = nil; Boolean allChannelsDiscrete = true; in...
Hello. I've been reading questions on Stack Overflow for a few weeks now... this'll be my first question. So recently I've looked into making C access/manipulate a C++ class. I understand that ideally one shouldn't compile components in C and C++ separately under normal circumstances, but this isn't an option at the moment. I looked in...
I have a c code about 1200 lines long and i want to convert it into matlab. is there any software or website where i can do it. ...
At the moment I am considering whether or not to rewrite a programming language interpreter that I maintain in C++. The interpreter is currently implemented in C. But I was wondering, is the primary implementationbecause, certainly, people have made versions of many interpreters using a language other than the one used by the original a...
I'm using a library (ANet) which is written natively in C and I am interfacing with it using C# via a small subset wrapper dll which i've made in C and statically links to it. The library (ANet) has a DllMain which simply tracks the number of references to it (so "Process attach" and "Thread attach" counts) but it seems to go into the ne...
Hey, I need to generate a path string from a number (in C) e.g: 53431453 -> 0003/2F4/C9D what I have so far is this: char *id_to_path(long long int id, char *d) { char t[MAX_PATH_LEN]; sprintf(t, "%010llX", id); memcpy(d, t, 4); memcpy(d+5, t+4, 3); memcpy(d+9, t+7, 4); d[4] = d[8] = '/'; return ...
Possible Duplicate: What does unsigned temp:3 means I'm learning some kernel code, and came along the following line (in linux 2.4, sched.h, struct mm_struct): unsigned dumpable:1; What does this mean? ...
Hello, I need to store a graph for the map of a game inside a game server written in C. The graph has ~200 nodes and 3 kinds of edges that can connect two nodes (these three kind can also overlap: a node can be connected by 2 edges of two different types for example). The maximum degree of a node is something like 5-6 nodes. What I wou...
char *a=NULL; char *s=NULL; a=(char *)calloc(1,(sizeof(char))); s=(char *)calloc(1,(sizeof(char))); a="DATA"; memcpy(s,a,(strlen(a))); printf("%s",s); Can you plz tell me why its printing DATA½½½½½½½½■ε■????How to print only DATA?? Thanks ...
I have following code int wordLenght = 256, arrayLength = 2, i = 0, counter = 0; char **stringArray = NULL; stringArray = calloc(arrayLength, sizeof(*stringArray)); for(counter; counter<wordLenght; counter++) stringArray[counter] = calloc(wordLenght, sizeof(stringArray)); while(1) { printf("Input: "); fgets(stringAr...
/* It is not entering data into the third scanf() statement .*/ #include<stdio.h> #include<conio.h> #include<string.h> void main(void) { struct book { char name; int pages; float price; }; struct book a1,a2,a3,a4; printf("Enter data into 3 books\n"); scanf("%c %d %f",&a1.name,&a1.pages,&a...
What's the best/recommended way to copy data between a byte array and an integer in C? Currently I'm using memcpy, which doesn't feel right to me. A sample of the sort of thing I'm doing is below. struct alpha { unsigned char byte_array[20]; } void function(struct alpha *st) { unsigned long num; /* Do some stuf...
In c++, setw function is used to set the number of characters to be used as the field width for the next insertion operation. Is there any function in C, I mean, in standard c library, which does the same thing? ...
Hello everyone! For school I have to program a merge sort using only pointers. I've tried almost everything, but I can not get it working. #include <stdio.h> #include <stdlib.h> #include <string.h> #define num_elementi(array) (sizeof(array)/sizeof(array[0])) void selsort(int arr[],int n); void swap(int * a, int * b); void print(int a...