How can we get and handle the sftp return codes in a C program if sftp fails to put the file in a server? We need to transfer the files again if sftp fails to put it in the sftp server. ...
I would like to create a wireless network from a laptop. If laptops come within range, I would like it to send them a welcome message and send them a goodbye message when they leave the wifi range. Is it possible to do this in C? Please help me out with this. ...
I am getting an error message "expression must have constant value" when initializing an array of structures with an external constant integer. File1.c: const unsigned char data1[] = { 0x65, 0xF0, 0xA8, 0x5F, 0x5F, 0x5F, 0x5F, 0x31, 0x32, 0x2E, 0x31, 0xF1, 0x63, 0x4D, 0x43, 0x52, 0x45, 0x41, 0x54, 0x45, 0x44, 0x20,...
I can't seem to get a simple program (with lots of memory access) to achieve consistent timing in Linux. I'm using a 2.6 kernel, and the program is being run on a dual-core processor with realtime priority. I'm trying to disable cache effects by declaring the memory arrays as volatile. Below are the results and the program. What are some...
Hi I wanted to try out the splice syscall. I have this function - it should copy content of one file to another: static void test_splice( int in, int out ) { int i = 0, rcvd = 0; int filedes[2]; off_t off = 0; if ( pipe( filedes ) < 0 ) { perror( "Kicha pipe" ); exit( EX...
Question says it all. Does anyone know if the following... size_t div(size_t value) { const size_t x = 64; return value / x; } ...is optimized into? size_t div(size_t value) { return value >> 6; } Do compilers do this? (My interest lies in GCC). Are there situations where it does and others where it doesn't? I would re...
How to use compiled LibPng sample? I have compiled it (lib png) now I want to use it with bitmap data. Can any one please share some simple AS code for USING compiled lib png? ...
Hi All, I am reading the contents of the file using fread into an char array. But I am not sure why it is not getting printed in the output. Here is the code: void getInfo(FILE* inputFile) { char chunk[4]; int liIndex; for (liIndex = 0 ; liIndex < 4 ; liIndex++) { fread(chunk, sizeof(char), 4, inputFile); } prin...
I have a function using strtok like this void f1(char *name) { ... char *tmp; tmp = strtok(names, " ,"); while(tmp) { ... tmp = strtok(NULL, " ,"); } ... } And i have a call f1("abc,def"); Problem is that in first call f1 gets abc,def and in 2nd call gets just abc I am confused.. Why is this so? ...
I've decided to do it this way flip numbers 0=1, 1=0 add 1 to LSB if carry, loop until array[i]==0 But I'm stuck on the last point; how can I say that in a conditional loop? ...
According to the responses in "Why subtract null pointer in offsetof()?" (and my reading of K&R), the C standard doesn't require that (size_t)((char *)0) == 0. Still, I've never seen a situation where casting a null pointer to an integer type evaluates to anything else. If there is a compiler or scenario where (size_t)((char *)0) != 0, ...
Here is my code: #include <stdio.h> int main(void) { FILE *fp; unsigned int i; char bytes[512]; fp = fopen("myFile","r"); for(i = 0;i <= 512;i++) { fread(&bytes, sizeof(bytes), 1, fp); printf("bytes[%d]: %x\n", i, bytes[i]); } } Here is the expected outp...
Hello, I have a windows form that has a simple menu and performs a simple operation, I want to be able to create another windows form with all the functionality of a menu bar, message pump etc.. as a separate thread so I can then share the results of the operation to the second window. I.E. 1) Form A opens Form B opens as a separate t...
Something that has piqued my interest is Objective-C's BOOL type definition. Why is it defined as a signed char (which could cause unexpected behaviour if a value greater than 1 byte in length is assigned to it) rather than as an int, as C does (much less margin for error: a zero value is false, a non-zero value is true)? The only re...
I have a structure: struct mystruct { int* pointer; }; structure mystruct* struct_inst; Now I want to change the value pointed to by struct_inst->pointer. How can I do that? EDIT I didn't write it, but pointer already points to an area of memory allocated with malloc. ...
I want to add a few drawing functions to an iPhone project for drawing things. Something like drawTile(x,y,len,wid); which would call openGL to draw a box somewhere. I should just be able to write a procedural C file to do this but the openGL libraries are objective C and I'm getting weird errors. Do I have to make a class for all of my ...
Does anyone know how to open an image, specifically a jpg, to a byte array in C or C++? Any form of help is appreciated. Thanks! ...
Hi guys! I realize it's probably something strange, but here is what I have. I have an application (handwriting recognition engine) written in C/C++. This application has Perl wrapper which was made by application's authors using SWIG. My website is written in PHP, so I'm looking for some ways to make PHP work with C/C++ application. ...
I'm doing some specific signal analysis, and I am in need of a method that would smooth out a given bell-shaped distribution curve. A running average approach isn't producing the results I desire. I want to keep the min/max, and general shape of my fitted curve intact, but resolve the inconsistencies in sampling. In short: if given a se...
#include <pthread.h> #include <stdio.h> #include <stdlib.h> #define NUM_THREADS 4 #define TCOUNT 5 #define COUNT_LIMIT 13 int done = 0; int count = 0; int thread_ids[4] = {0,1,2,3}; int thread_runtime[4] = {0,5,4,1}; pthread_mutex_t count_mutex; pthread_cond_t count_threshold_cv; void *inc_count(void *t) { ...