std::recursive_mutex::lock
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< cpp | thread | recursive mutex
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void lock(); |
(desde C++11) | |
Bloqueia o mutex. Se outro segmento já tenha travado o mutex, uma chamada para
lock
irá bloquear a execução até que o bloqueio é adquirido.Original:
Locks the mutex. If another thread has already locked the mutex, a call to
lock
will block execution until the lock is acquired.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
A thread may call lock
on a recursive mutex repeatedly. Ownership will only be released after the thread makes a matching number of calls to unlock
.
The maximum number of levels of ownership is unspecified. An exception of type std::system_error will be thrown if this number is exceeded.
Índice |
[editar] Parâmetros
(Nenhum)
Original:
(none)
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[editar] Valor de retorno
(Nenhum)
Original:
(none)
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[editar] Exceções
Lança std::system_error quando ocorrem erros, incluindo erros do sistema operacional subjacente que impediriam
lock
de cumprir suas especificações.Original:
Throws std::system_error when errors occur, including errors from the underlying operating system that would prevent
lock
from meeting its specifications.The text has been machine-translated via Google Translate.
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[editar] Exemplo
Este exemplo mostra como
lock
unlock
e pode ser utilizado para proteger os dados compartilhados .
Original:
This example shows how
lock
and unlock
can be used to protect shared data.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
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#include <iostream> #include <chrono> #include <thread> #include <mutex> int g_num = 0; // protected by g_num_mutex std::mutex g_num_mutex; void slow_increment(int id) { for (int i = 0; i < 3; ++i) { g_num_mutex.lock(); ++g_num; std::cout << id << " => " << g_num << '\n'; g_num_mutex.unlock(); std::this_thread::sleep_for(std::chrono::seconds(1)); } } int main() { std::thread t1(slow_increment, 0); std::thread t2(slow_increment, 1); t1.join(); t2.join(); }
Potencial saída:
0 => 1 1 => 2 0 => 3 1 => 4 0 => 5 1 => 6
[editar] Veja também
tenta bloquear o mutex, retorna se o mutex não está disponível Original: tries to lock the mutex, returns if the mutex is not available The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (função pública membro) | |
destrave o mutex Original: unlocks the mutex The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (função pública membro) |