mirror of https://github.com/davisking/dlib.git
72 lines
1.5 KiB
C++
72 lines
1.5 KiB
C++
// The contents of this file are in the public domain. See LICENSE_FOR_EXAMPLE_PROGRAMS.txt
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/*
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This is a very simple example that illustrates the use of the
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thread_function object from the dlib C++ Library.
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The output of the programs should look like this:
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45.6
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9.999
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I have no args!
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val: 3
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*/
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#include <iostream>
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#include "dlib/threads.h"
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#include "dlib/ref.h"
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using namespace dlib;
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using namespace std;
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void thread_1(double a)
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{
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cout << a << endl;
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}
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void thread_2 ()
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{
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cout << "I have no args!" << endl;
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}
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void thread_increment(double& a)
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{
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a += 1;
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}
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int main()
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{
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// create a thread that will call thread_1(45.6)
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thread_function t1(thread_1,45.6);
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// wait for the t1 thread to end
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t1.wait();
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// create a thread that will call thread_1(9.999)
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thread_function t2(thread_1,9.999);
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// wait for the t2 thread to end
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t2.wait();
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// create a thread that will call thread_2()
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thread_function t3(thread_2);
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// Note that we can also use the ref() function to pass a variable
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// to a thread by reference. For example, the thread below adds
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// one to val.
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double val = 2;
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thread_function t4(thread_increment, dlib::ref(val));
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t4.wait(); // wait for t4 to finish before printing val.
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// Print val. It will now have a value of 3.
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cout << "val: " << val << endl;
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// At this point we will automatically wait for t3 to end because
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// the destructor for thread_function objects always wait for their
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// thread to terminate.
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}
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