May be it look childish for most of you but I am unable to understand this small piece of code. #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/types.h> #include <sys/wait.h> int main(int argc, char** argv) { int i, pid; pid = fork(); printf("Forking the pid: %d\n",pid); for(i =0; i<5; i++) ...
I want to fix problem reported by valgrind: ==7182== Conditional jump or move depends on uninitialised value(s) ==7182== at 0x40EC75C: strstr (in /lib/libc-2.9.so) ==7182== by 0x804A977: search_graph_begin (compression.c:462) ==7182== by 0x804AB60: search_graph_end (compression.c:497) ==7182== by 0x804AA97: search_graph_be...
Just trying to copy a file using CopyFile() function from the current directory to C:\windows\system32\drivers. I wrote also manifest with "requestedExecutionLevel level="highestAvailable"" in it and I run mt to add it to resulting executable. When I try to run it, Windows 7 UAC dialog popping out, I press "Yes", but CopyFile() returni...
In C, is it possible to define a union within another union? If no, why is it not possible? Or if yes, where can it be used? ...
Hi, I have a C function in which I have 4 pointers and each of them point to different locations of a large 2D array of floats. Because the ARM assembly functions can only be passed with 4 parameters (r0 - r3), I'm not able to understand how to pass the pointer to my return value, which will become the 5th parameter to my assembly func...
Hello, gcc 4.4.4 c89 I am just wondering why I am getting different memory address. When I print the address of animals in main I get the following: animals [ rabbit ] : [ 0xbfab2e48 ] animals [ rabbit ] : [ 0xbfab2e48 ] However, when I print in the function, I get different memory locations. I think they should be the same. ptr an...
Is it possible to change the number of bytes a long has in visual studio? Currently when compiling C code sizeof(int) and sizeof(long) are both equal to 4. ...
Hello, QueryDosDevice(L"E:", DeviceName, MAX_PATH); (E: is a SD card) DeviceName is "\Device\HarddiskVolume3" How do I "convert" it to something like "\\.\PHYSICALDRIVE1" ...
In C++ and Java, data structures can have private, public and protected regions. I'd like to port this concept to a C language program I am writing. Are there any idioms for implementing private or protected function pointers and data fields in a C struct? I know that C structs are public, I'm looking for an idiom to help hide some i...
I have a function getNum(), which gets a number from file and returns it. When I go back into getNum() I have lost the pointer and it starts at the begging of the file again. I'm wondering How do I get the location of where getc is and then go back to that place. I couldn't find how to do this in the manual or in forums. Thank you. #inc...
Hi, I'm new at programming, new on this site too, so hello... I'm attempting to obtain a running total for integers one thru 10, but I'm getting gibberish answers and I just can't understand why. To attempt to find out what was going wrong, I added the printf(" running total is %d\n", sum); line to the while loop, but just got more o...
I'm attempting to exit a while loop, based on file contents. File exists and is empty, or garbage filled at initialization of the program. I externally modify the file, and would like the loop to exit upon this happening based on how the file was modified. Currently, I start a few threads, open the file that I'm reading from. Check the ...
Hi, Sometimes in execution I get this error message in VS2010 when trying to free memory: Windows has triggered a breakpoint in [APPNAME].exe. This may be due to a corruption of the heap, which indicates a bug in [APPNAME].exe or any of the DLLs it has loaded. This may also be due to the user pressing F12 while [APPNAME].e...
I have a project that consists of a bunch of dynamically loaded modules. Originally, everything was always built with MSVC 2003, but lately I've been working on getting it to work with GCC. Everything has been going pretty smoothly, except for one problem. For 64-bit code, GCC and MSVC don't agree about what a va_list is. For 32-bit,...
I was stracing some of the common commands in the linux kernel, and saw mprotect() was used a lot many times. I'm just wondering, what is the deciding factor that mprotect() uses to find out that the memory address it is setting a protection value for, is in its own address space? ...
Hi there, Actually I've (probably) a "simple" problem. So I don't know how to cast a signed integer to an unsigned integer. My code : signed int entry = 0; printf("Decimal Number : "); scanf("%d", &entry); unsigned int uEntry= (unsigned int) entry; printf("Unsigned : %d\n", uEntry); If I send the unsigned value to the console (see...
Suppose I want to read an entire file in memory. I'd open it in binary mode, use fseek to get to the end of the file, then do ftell to get its size. Then I would allocate a string with the same size as the file, and just read it in, right? The problem is that ftell returns a long int, and malloc should receive a size_t argument. Now, si...
I'm wondering what sort of algorithm could be used to take something like "4.72" into a float data type, equal to float x = 4.72; ...
In a recent code review, a contributor is trying to enforce that all NULL checks on pointers be performed in the following manner: int * some_ptr; // ... if( some_ptr == NULL ) { // handle null-pointer error } else { // proceed } instead of int * some_ptr; // ... if( some_ptr ) { // proceed } else { //handle null-pointer err...
Is there a method to return the identifier string for a given element's numerical value? For instance, logging a UITouch's phase returns an int, but having the actual string value would be easier to read. I suppose I could write my own switch statement to do this, but I'm hoping there's a built-in means. ...