c

问题 I'm creating a program that reads in input from a midi controller using libusb. How do I properly call libusb_bulk_transfer? Currently I'm receiving the error "LIBUSB_ERROR_NOT_FOUND" every time, and the data that I receive is "P". I've swapped out the function 'libusb_bulk_transfer' with 'libusb_interrupt_transfer' but I still receive the same error: LIBUSB_ERROR_NOT_FOUND Below are the libraries that I currently have included #include <stdlib.h> #include <stdio.h> #include <libusb-1.0

问题 I'm creating a program that reads in input from a midi controller using libusb. How do I properly call libusb_bulk_transfer? Currently I'm receiving the error "LIBUSB_ERROR_NOT_FOUND" every time, and the data that I receive is "P". I've swapped out the function 'libusb_bulk_transfer' with 'libusb_interrupt_transfer' but I still receive the same error: LIBUSB_ERROR_NOT_FOUND Below are the libraries that I currently have included #include <stdlib.h> #include <stdio.h> #include <libusb-1.0

问题 I'm trying to redirect stdout so that printf in a windows application will go to a file of my choice. I'm doing this: outFile = fopen("log.txt", "w"); *stdout = *outFile; setvbuf(stdout, NULL, _IONBF, 0); but printf still writes to the console (or nowhere on a GUI based win32 application) I can redirect 'std::cout' by doing this: outFileStr = std::ofstream(outFile); std::cout.rdbuf(outFileStr.rdbuf()); But printf seems to be doing its own thing. Unfortunately, I need to redirect printf as I'm

问题 Closed . This question needs details or clarity. It is not currently accepting answers. Want to improve this question? Add details and clarify the problem by editing this post. Closed 11 months ago . Improve this question I know using recursions way but it works just for loops which beginning and ending statements are same like code below for (int i=1 ; i<5;i++){ for (int j=0; j<5;j++){ for (int m= 0;m<5;m++) { // N time } } } But my problem is different. I do not know N level and beginning

问题 I've got some C code from a 3rd party vendor (for an embedded platform) that uses global variables (for speed & space optimizations). I'm documenting the code, converting to Doxygen format. How do I put a note in the function documentation that the function requires on global variables and functions? Doxygen has special commands for annotating parameters and return values as describe here: Doxygen Special Commands. I did not see any commands for global variables. Example C code: extern

问题 I've got some C code from a 3rd party vendor (for an embedded platform) that uses global variables (for speed & space optimizations). I'm documenting the code, converting to Doxygen format. How do I put a note in the function documentation that the function requires on global variables and functions? Doxygen has special commands for annotating parameters and return values as describe here: Doxygen Special Commands. I did not see any commands for global variables. Example C code: extern

问题 I've got some C code from a 3rd party vendor (for an embedded platform) that uses global variables (for speed & space optimizations). I'm documenting the code, converting to Doxygen format. How do I put a note in the function documentation that the function requires on global variables and functions? Doxygen has special commands for annotating parameters and return values as describe here: Doxygen Special Commands. I did not see any commands for global variables. Example C code: extern

问题 I've got some C code from a 3rd party vendor (for an embedded platform) that uses global variables (for speed & space optimizations). I'm documenting the code, converting to Doxygen format. How do I put a note in the function documentation that the function requires on global variables and functions? Doxygen has special commands for annotating parameters and return values as describe here: Doxygen Special Commands. I did not see any commands for global variables. Example C code: extern

问题 I'm attempting to write a program in C which finds the numeric value of the second derivative of f(x) where x is given. When I use my function to find the first derivative, everything seems to be working okay, but the recursive second derivative part always gives me 0.0. Here's my function: double derivative(double (*f)(double), double x0, int order) { if(order == 1){ const double delta = 1.0e-6; double x1 = x0-delta; double x2 = x0+delta; double y1 = f(x1); double y2 = f(x2); return (y2 - y1

问题 I'm a beginner and I am making a code about getting the directory of a file, but I have something that I don't understand. What's the meaning of "./" in DS = opendir ("./"); I have searched a lot of sites about C programming, but nothing gave me a good explanation. I have to present my code soon, forcing me to explain every single line of my code. Please help me. Thanks! 回答1: ./ is a relative path which is relative to the current working directory of your process. In computing, the working