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Questions tagged [stdthread]

std::thread is a C++11 standard library class which represents a single thread of execution. Threads allow multiple functions to execute concurrently.

std::thread is a C++11 standard library type which creates a new thread and runs a function (or other callable object) in that new thread.

Include the <thread> header to use std::thread.

C++20 added std::jthread which automatically .join()s the thread on destruction instead of std::terminate()ing, a generally preferable behavior.

593 questions
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How does this simple multithread code lead to memory corruption?

The following code reliably produces a segfault. #include #include class Class { public: Class(const int integer) : cinteger(integer), carray(std::array{0}) {} const int operator()() { …
Takirion
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Why does std::this_thread::get_id() function returns the same number in CentOS?

In the following code, the .get_id() call returns the same value when run on CentOS; but on Windows, the same code returns different values. Why? #include #include #include void dosomework() { std::cout <<…
JY Lee
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c++ lambda function calls pure virtual function

I am trying to create a wrapper class for std::thread. This class provides a kick method which starts the thread and calls a pure virtual function. I am using a derived class to call this kick method and derived class also has implemented the…
theadnangondal
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Can one retrieve the return value of a thread function in C++11?

If a function has a non-void return value and I join it using the .join function then is there any way to retrieve its return value? Here is a simplified example: float myfunc(int k) { return exp(k); } int main() { std::thread…
Reza
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c++11 threads vs async

Consider the following two snippets of code where I am trying to launch 10000 threads: Snippet 1 std::array, 10000> furArr_; try { size_t index = 0; for (auto & fut : furArr_) { …
Arun
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How to get thread object by id?

Let's say that some thread has std::thread::id myId of some other thread. Now I want to retrieve the std::thread object associated with myId so I can .join() it. Is it possible in std? Or do I have to track it manually?
freakish
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Is it safe to never retrieve the result of a std::future from a std::packaged_task?

Is it safe to create a std::future from a std::packaged_task, which executes on a separate thread, but not always retrieve its result? #include #include class Result { Result() {} ~Result() {} }; void foo() { …
Pol
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Retrieve the Windows thread identifier from the std::thread::id structure

I have access to a std::thread::id in my code, and need to use some native functions that receive as argument ThreadId as DWORD ( same as returned by GetCurrentThreadId() ). I cannot find any way to convert from std::thread::id to a Win32 DWORD…
cprogrammer
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Assigning a new task to a thread after the thread completes in C++

I have the following code in C++. The code is from C++ Concurrency In Action: Practical Multithreading void do_work(unsigned id); void f() { std::vector threads; for(unsigned i = 0; i < 20; ++i) { …
Mutating Algorithm
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Launching runnable objects in threads out of a C++ std::vector

I have a C++11 program which configures a number of runnable objects, puts them in a std::vector, then launches them all in separate threads. Unfortunately when I iterate over the objects in the vector, I am getting threads launched only for the…
lcikgl
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Perfect Forwarding Variadic Template to Standard Thread

I'm trying to make a form of std::thread that puts a wrapper around the code executed in the thread. Unfortunately I can't get it to compile due likely to my poor understanding of rvalues and the Function templated type I'm trying to pass. Here's my…
zmoratto
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C++ 11 : Start thread with member function and this as parameter

Using this code, I got and error : Error 1 error C2064: term does not evaluate to a function taking 1 arguments c:\program files (x86)\microsoft visual studio 11.0\vc\include\functional 1152 1 Pipeline class PipelineJob { private: …
user1401072
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How standard is std::thread?

I've noticed that on a lot of the classic C++ reference sources that HAVE been updated for C++11, such as cplusplus.com and the Josuttis Standard Library Reference book, don't seem to cover / have any documentation at all on the C++11 concurrency…
David Adrian
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timeout in std::async

Is there a way to implement timeout in the std::async method, so I want this call to timeout and complete if the thread hasnt completed for the specified amount of time. How can I implement this functionality.
Adobri
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A parallel for using std::thread?

I'm new with std::thread and I try to code a parallel_for. I coded the following thing: // parallel_for.cpp // compilation: g++ -O3 -std=c++0x parallel_for.cpp -o parallel_for -lpthread // execution: time ./parallel_for 100 50000000 // (100: number…
Vincent
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