The scope of semaphore (process/thread).

• thread = 0
• process = 1

Semaphore, implemented using POSIX system calls. Suitable for both processes and threads.

Derived classes

• sys::process_semaphore
• sys::thread_semaphore

Types

• using clock_type = std::chrono::system_clock

  Clock type used in this class.

Methods

• notify(int n) -> void

  Notify n processes that wait on this semaphore.

  bad_call

  
  

  See

  semop(2)

• notify_one() -> void

  Notify one process that wait on this semaphore.

  bad_call

  
  

  See

  semop(2)

• template <class Lock, class Clock, class Duration, class Pred>
wait_until(Lock & lock, const std::chrono::time_point< Clock, Duration > & tp, Pred pred) -> bool

  Wait on the semaphore until specified time dur unlocking lock for the duration of the wait until predicate pred becomes true or timeout occurs.

  bad_call

  
  

  • If pred is true upon the call to this method no waiting or unlocking is done
  • The mutex is locked when checking for the predicate.

  Return

  predicate value

  See

  semtimedop(2)

• template <class Lock, class Clock, class Duration>
wait_until(Lock & lock, const std::chrono::time_point< Clock, Duration > & tp) -> std::cv_status

  Wait on the semaphore until specified time tp unlocking lock for the duration of the wait.

  bad_call

  
  

  See

  semtimedop(2)

  See

  sem_timedwait(2)

• template <class Lock, class Duration, class Pred>
wait_until(Lock & lock, const std::chrono::time_point< clock_type, Duration > & tp, Pred pred) -> bool

  Wait on the semaphore until specified time tp unlocking lock for the duration of the wait until predicate pred becomes true.

  bad_call

  
  

  • If pred is true upon the call to this method no waiting or unlocking is done
  • The mutex is locked when checking for the predicate.

  Return

  predicate value

  See

  sem_timedwait(2)

• template <class Lock, class Duration>
wait_until(Lock & lock, const std::chrono::time_point< clock_type, Duration > & tp) -> std::cv_status

  Wait on the semaphore until specified time tp unlocking lock for the duration of the wait.

  bad_call

  
  

  See

  sem_timedwait(2)

• template <class Lock, class Rep, class Period, class Pred>
wait_for(Lock & lock, const std::chrono::duration< Rep, Period > & dur, Pred pred) -> bool

  Wait on the semaphore specified amount of time dur unlocking lock for the duration of the wait until predicate pred becomes true or timeout occurs.

  bad_call

  
  

  • If pred is true upon the call to this method no waiting or unlocking is done
  • The mutex is locked when checking for the predicate.

  Return

  predicate value

  See

  semtimedop(2)

  See

  sem_timedwait(2)

• template <class Lock, class Rep, class Period>
wait_for(Lock & lock, const std::chrono::duration< Rep, Period > & dur) -> std::cv_status

  Wait on the semaphore specified amount of time dur unlocking lock for the duration of the wait.

  bad_call

  
  

  See

  semtimedop(2)

  See

  sem_timedwait(2)

• template <class Lock, class Pred>
wait(Lock & lock, Pred pred) -> void

  Wait on the semaphore unlocking lock for the duration of the wait until predicate pred becomes true.

  bad_call

  
  

  • If pred is true upon the call to this method no waiting or unlocking is done
  • The mutex is locked when checking for the predicate.

  See

  semop(2)

  See

  sem_wait(2)

• template <class Lock>
wait(Lock & lock) -> void

  Wait on the semaphore unlocking lock for the duration of the wait.

  bad_call

  
  

  See

  semop(2)

  See

  sem_wait(2)

• wait() -> void

  Wait until other process/thread calls sysv_semaphore::notify_one or sysv_semaphore::notify on this semaphore.

  bad_call

  
  

  See

  semop(2)

  See

  sem_wait(2)

• ~posix_semaphore()
• posix_semaphore(semaphore_type type)explicit

  Construct semaphore with specified type.

  bad_call

  
  

Semaphore, implemented using System V system calls. Suitable for both processes and threads.

Types

• using clock_type = std::chrono::system_clock

  Clock type used in this class.

• using sem_type = int

  Alias to system semaphore type (int).

Methods

• template <class Lock, class Clock, class Duration, class Pred>
wait_until(Lock & lock, const std::chrono::time_point< Clock, Duration > & tp, Pred pred) -> bool

  Wait on the semaphore until specified time dur unlocking lock for the duration of the wait until predicate pred becomes true or timeout occurs.

  bad_call

  
  

  • If pred is true upon the call to this method no waiting or unlocking is done
  • The mutex is locked when checking for the predicate.

  Return

  predicate value

  See

  semtimedop(2)

• template <class Lock, class Clock, class Duration>
wait_until(Lock & lock, const std::chrono::time_point< Clock, Duration > & tp) -> std::cv_status

  Wait on the semaphore until specified time tp unlocking lock for the duration of the wait.

  bad_call

  
  

  See

  semtimedop(2)

• template <class Lock, class Duration, class Pred>
wait_until(Lock & lock, const std::chrono::time_point< clock_type, Duration > & tp, Pred pred) -> bool

  Wait on the semaphore until specified time tp unlocking lock for the duration of the wait until predicate pred becomes true.

  bad_call

  
  

  • If pred is true upon the call to this method no waiting or unlocking is done
  • The mutex is locked when checking for the predicate.

  Return

  predicate value

  See

  semtimedop(2)

• template <class Lock, class Duration>
wait_until(Lock & lock, const std::chrono::time_point< clock_type, Duration > & tp) -> std::cv_status

  Wait on the semaphore until specified time tp unlocking lock for the duration of the wait.

  bad_call

  
  

  See

  semtimedop(2)

• template <class Lock, class Rep, class Period, class Pred>
wait_for(Lock & lock, const std::chrono::duration< Rep, Period > & dur, Pred pred) -> bool

  Wait on the semaphore specified amount of time dur unlocking lock for the duration of the wait until predicate pred becomes true or timeout occurs.

  bad_call

  
  

  • If pred is true upon the call to this method no waiting or unlocking is done
  • The mutex is locked when checking for the predicate.

  Return

  predicate value

  See

  semtimedop(2)

• template <class Lock, class Rep, class Period>
wait_for(Lock & lock, const std::chrono::duration< Rep, Period > & dur) -> std::cv_status

  Wait on the semaphore specified amount of time dur unlocking lock for the duration of the wait.

  bad_call

  
  

  See

  semtimedop(2)

• template <class Lock, class Pred>
wait(Lock & lock, Pred pred) -> void

  Wait on the semaphore unlocking lock for the duration of the wait until predicate pred becomes true.

  bad_call

  
  

  • If pred is true upon the call to this method no waiting or unlocking is done
  • The mutex is locked when checking for the predicate.

  See

  semop(2)

• template <class Lock>
wait(Lock & lock) -> void

  Wait on the semaphore unlocking lock for the duration of the wait.

  bad_call

  
  

  See

  semop(2)

• notify(int n) -> void

  Notify n processes that wait on this semaphore.

  bad_call

  
  

  See

  semop(2)

• notify_one() -> void

  Notify one process that wait on this semaphore.

  bad_call

  
  

  See

  semop(2)

• wait() -> void

  Wait until other process/thread calls sysv_semaphore::notify_one or sysv_semaphore::notify on this semaphore.

  bad_call

  
  

  See

  semop(2)

• owner() const -> bool

  Check if this semaphore is owned by this process.

• id() const -> sem_type

  Get semaphore ID.

• ~sysv_semaphore()

  Remove semaphore (if owner). Terminates on system error.

  See

  semctl(2)

• sysv_semaphore(sem_type sem)explicit

  Construct semaphore with ID sem. The semaphore is not owned by the calling process/thread.

• sysv_semaphore(mode_type mode = 0600)explicit

  Construct semaphore with specified mode.

  bad_call

  
  

  The semaphore is owned by the calling process/thread.

  See

  semget(2)