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I recently learned something from this question about cin in C++ and its speed was compared with the speed of scanf in C. Calling cin object is much slower than calling scanf function as usual but when I was reading the accepted answer, I understood if we call std::ios::sync_with_stdio(false);, cin synchronization with scanf is turned off and cin speed becomes so faster and even faster than scanf in this case.

So, will we face some problems if we turn it off? If so, what problems, and is it good to turn off cin synchronization with scanf in C? Thanks for helping.

I've installed Microsoft VSCode under Linux Mint, and opened a folder named test1 containing 3 files:

test.cpp - pre-declares foo() and bar(), then calls both functions in main()
foo.cpp - defines function foo()
bar.cpp - defines function bar()

When I compile test.cpp (using F5 Start debugging in VSCode) it fails with undefined reference to foo() and undefined reference to bar(). When I compile foo.cpp and bar.cpp, they both fail with undefined reference to main.

I found VS Code will not build c++ programs with multiple .ccp source files as asked here previously, from which I discover I can type the following in the VSCode "Terminal" window...

g++ test.cpp foo.cpp bar.cpp -o a.out
./a.out

...and my program compiles and runs as expected (but I can't do any debugging, obviously).

So what I want to know in the first instance is How do I tell VSCode to compile and link in those two additional source files?

Unless it's going to be blindingly difficult, I'd also like some guidance on how to go about moving on to Phase 2 of my task - compiling foo and bar into a "library" file that I can link across to when working on a project in folder test2 (sibling to test1).

If at all possible, I'd like to achieve this entirely within the context of the VSCode environment (maybe I'll think about learning the complexities of g++ and makefiles sometime in the future).

Thanks for answering my question. I am working for a project recently. In this project, I write a shared library and set the LD_PRELAOD to the shared library's path. I want to intercept some programs' system calls by using this shared library, such as socket(), bind(), send(). It works for C-programs and Python-programs, but it doesn't work for Golang-programs. Later I know that Go-programs comply with the static libraries. So I tried this command: go build -linkshared , unlucky, it failed. Finally, I use the command nm to check the symbols in the application. And I found these:

I'm writing a program said in this post title. I take reference at this webpage.

https://www.includehelp.com/c-programs/c-program-to-print-given-number-of-lines-of-a-file-like-head-command-in-linux.aspx

Here are the codes from that webpage.

I got this code from another answer to a similar question, but I can't figure out why this is not working for me. The test.csv is in the same folder as the compiled .exe file, but it doesn't find it. I tried the full system path ("C:\Users\hhv\eclipse-workspace\oncemore\Debug\test.csv") but it still fails to open the csv.

So I am at a lose over what's going on because every other example I have looked at looked like this should be working. Ex: https://github.com/tpatil2/C-Programs/blob/master/RWcsv/rwcsv.cpp

c++ reading csv file

I am using async await in WPF on the UI-Thread. I have a question on how async await works in a certain scenario. I will try to explain it on an example.

Let's assume I have the Button A with click event handler ButtonA_Click() and Button B with ButtonB_Click(). The click handlers will check if the RunLoop() method is still running. If it is not running, they start RunLoop().

1. Will the event handler return from the UI-Thread when (the outer) await RunLoop() is called?
2. Or will it return at the (inner) await in RunLoop() because there is synchronous code (_isStopped = false;) it could perform in the beginning of Runloop().

If 1. is true, it could cause a racing condition, or? When both click handlers are called at the same time, they will run right after each other on the UI-Thread. So the second event handler may run before RunLoop() can be executed for the first time. In this case _isStopped would still be false for the 2nd event handler and it would start a RunLoop(), too. Thus 2 RunLoop() would be active. Is that correct?

(PS: I know, that if 1. is the case, I can solve this by putting _isStopped = false into the click handlers, but this question is more about understanding how async await works when the methods are nested this way).

I have a Makefile that compiles two Linux kernel modules (mod1.c and mod2.c).

So, I am starting to familiarize with C, and at this point I'm trying to understand pointers. I got the following code from here, but I cannot comprehend, how does one subtract a character array from a pointer.

I need to compile some c-programs using cfitsio library in Google colab, in my mac I can do following: