On Windows, char c; int i; scanf("%d", &i); scanf("%c", &c); The computer skips to retrieve character from console because '\n' is remaining on buffer. However, I found out that the code below works well. char str[10]; int i; scanf("%d", &i); scanf("%s", str); Just like the case above, '\n' is remaining on buffer but why scanf s...
Some code: typedef struct _WDF_USB_DEVICE_SELECT_CONFIG_PARAMS { ULONG Size; WdfUsbTargetDeviceSelectConfigType Type; union { struct { PUSB_CONFIGURATION_DESCRIPTOR ConfigurationDescriptor; PUSB_INTERFACE_DESCRIPTOR* InterfaceDescriptors; ULONG NumInterfaceDescriptors; } Descriptor; struct { PUR...
Hi guys I hope anyone can help me. I'm running a simple program in C, running in Solaris 8, and I found a problem while using popen/pclose. FILE * stream; stream = popen("ps -ef | grep "pattern"); if(pclose(stream)){ printf("Erro no fechamento da stream\n"); } The pattern in grep command it's just a filter that I use to treat...
Can anyone illustrate the use of settimer or alarm function in gnu C , with some program examples ,please ? I have a program that continuously processes some data , and i need to set a timer / alarm that goes off every t seconds , in response to which , i need to store the processed data into a file. This file writing has to be asynchro...
I have a shared C library, libfoo.so, for which I'm creating a JNI interface. In order to compile the JNI interface library, libfoojni.so, compiler include search paths must be specified. For example, on Linux (using GCC) the following compiler flags are required: -I${JAVA_HOME}/include -I${JAVA_HOME}/include/linux. Unfortunately, the l...
My task is to checkpoint and restart X11 applications. Therefore I use the BLCR (Berkeley Lab Checkpoint/Restart (BLCR)) tool. Due to the fact that BLCR is not able (without modifications) to reinitiate the connection to the X-Server, I used an interposition library to log all Xlib function calls with their parameters to a text file. ...
Hey I'm looking for an XML parser for C/C++, just a parser which I give a string as an argument and it returns me a parsed document represented by a class/struct. The problem is that I am compiling it for the ARM9 processor and I need really just simple code no ./configure and stuff like that and no specific Makefile, just some files wh...
Background: I've been tasked with writing a data collection program for a Unitech HT630, which runs a proprietary DOS operating system that can run executables compiled for 16-bit MS DOS, albeit with some restrictions. I'm using the Digital Mars C/C++ compiler, which seems to be working very well. For some things I can use standard C l...
Hello I have been using LibTomCrypt to use SHA1 encryption ( for data integrity checking ) on mobile devices (iPhone OS and Android for the moment ). I was wondering if anyone is using anything else, things to consider are Portability ( C preferred but C++ is also an option ), and libraries size ( small == better for my particular needs ...
I've noticed on a number of occasions when refactoring various pieces of C and C++ code that a comma is used rather than a semi-colon to seperate statements. Something like this; int a = 0, b = 0; a = 5, b = 5; Where I would have expected int a = 0, b = 0; a = 5; b = 5; I know that C and C++ allow use of commas to seperate statem...
I have some question about cygwin : Can I use Cygwin develop socket based code? Does Cygwin have read() and write() functions that work with file descriptors? Can I use Pthread library in Cygwin? Does code that compiles in Cygwin also compile in Linux without any change or with little change? Will an executable file that built by Cyg...
I would like to know what the cons are of using the preprocessor in such a way: #define SOME_FUNCTION someFunction(someArgument) Basically I feel like this is wrong (or certainly not a best practice) - but I'm not sure why... my preprocessor skills are rusty at best. thanks, A ...
What's the most elegant way to return a std::list object from a shared lib function (implemented by C++ code) to a C consumer? I know for std::vector, we can return the address of the 1st element of the vector and have the consumer treat it as an array, but std::list is implemented as a linked lis. ...
I'm trying to give a Java application the ability to change the working directory within an active session of MATLAB. Basically, the user will press a button to launch MATLAB. Then, they will be able to press other buttons that change the working directory of the active MATLAB. I've tried a few different approaches, but with no luck. I'v...
I came across this in an IRC channel yesterday and didn't understand why it was bad behavior. #include <stdio.h> int main(void) { char x[sizeof(int)] = { '\0' }; int *y = (int *) x; printf("%d\n", *y); } Is there any loss of data or anything? can anyone give me any docs to explain further about what it does wrong? thanks! ...
I wrote an array_length function like this: int array_length(int a[]){ return sizeof(a)/sizeof(int); } However it is returning 2 when I did unsigned int len = array_length(arr); printf ("%i" , len); where I have int arr[] = {3,4,5,6,1,7,2}; int * parr = arr; But when I just do int k = sizeof(arr)/sizeof(int); printf("%i", ...
I have a program written in C that allows the user to scroll through a display of about a zillion small files. Each file needs to undergo a certain amount of processing (read only) before it's displayed to the user. I've implemented a buffer that preprocesses the files in a certain radius around the user's position, so if they're worki...
I'm very new to dealing with pointers, and my C knowledge is fairly small. I'm trying to understand pointers. I wrote the following code to print a list of variables (a to f) like so: 0 1 2 3 4 5 I wrote the following code to do this: #include <stdio.h> int main(){ int a,b,c,d,e,f; int *p; int i; a = b = c = d = f = 0; p = ...
What are the differences between const and volatile pointer in C? ...
Hi I have a BST binary search tree typedef struct Treenode *SearchTree; struct Treenode { int Element; SearchTree Left; SearchTree Right; }; and I want to create a function FillArray(int sizeoftree, tree, int array[]) And I want to use an array and copy the nodes of the tree in the array. How can I do this? the foll...