Difference between revisions of "cpp/atomic/atomic flag test and set"
From cppreference.com
(This example in atomic_flag is actually a test_and_set example, so it belongs here) |
m (fmt) |
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| Line 74: | Line 74: | ||
{ | { | ||
for(int cnt = 0; cnt < 100; ++cnt) { | for(int cnt = 0; cnt < 100; ++cnt) { | ||
| − | while(std::atomic_flag_test_and_set_explicit(&lock, std::memory_order_acquire)) | + | while(std::atomic_flag_test_and_set_explicit(&lock, std::memory_order_acquire)) |
| − | ; // spin | + | ; // spin until the lock is acquired |
std::cout << "Output from thread " << n << '\n'; | std::cout << "Output from thread " << n << '\n'; | ||
| − | std::atomic_flag_clear_explicit(&lock, std::memory_order_release); | + | std::atomic_flag_clear_explicit(&lock, std::memory_order_release); |
} | } | ||
} | } | ||
Revision as of 14:10, 4 January 2012
Template:cpp/atomic/sidebar Template:ddcl list begin <tr class="t-dsc-header">
<td>Defined in header
</td>
<atomic>
<td></td> <td></td> </tr> <tr class="t-dcl ">
<td >bool atomic_flag_test_and_set( volatile std::atomic_flag* p );
</td>
<td > (1) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">
<td >bool atomic_flag_test_and_set( std::atomic_flag* p );
</td>
<td > (2) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">
<td >bool atomic_flag_test_and_set_explicit( volatile std::atomic_flag* p,
std::memory_order order );
</td>
std::memory_order order );
<td > (3) </td> <td > (since C++11) </td> </tr> <tr class="t-dcl ">
<td >bool atomic_flag_test_and_set_explicit( std::atomic_flag* p,
std::memory_order order );
</td>
std::memory_order order );
<td > (4) </td> <td > (since C++11) </td> </tr> Template:ddcl list end
Atomically changes the state of a Template:cpp pointed to by p to set (Template:cpp) and returns the value it held before.
Contents |
Parameters
| p | - | pointer to Template:cpp to access |
| order | - | the memory sycnhronization ordering for this operation |
Return value
The value previously held by the flag pointed to by p
Exceptions
noexcept specification:
noexcept
