SysRWLReadLock (FUN) ¶ FUNCTION SysRWLReadLock : RTS_IEC_RESULT This function to enter a read lock(synchronization object). NOTE: Several readers can enter the lock simultaneously! But they are synchronized against an entered write lock! RETURN: Returns the runtime system error code (see CmpErrors.library) InOut: Scope Name Type Comment Return SysRWLReadLock RTS_IEC_RESULT Input hRWLock RTS_IEC_HANDLE Handle to the ReadWrite lock object created by SysRWLCreate

SysRWLReadLockTry (FUN) ¶ FUNCTION SysRWLReadLockTry : RTS_IEC_RESULT This function tries enter a read lock(synchronization object). If a write lock is still active, the functions returns an error. The function succeeded as well, if another read lock is still active. NOTE: Several readers can enter the lock simultaneously! But they are synchronized against an entered write lock! RETURN: Returns the runtime system error code (see CmpErrors.library) InOut: Scope Name Type Comment Return SysRWLReadLockTry RTS_IEC_RESULT Input hRWLock RTS_IEC_HANDLE Handle to the ReadWrite lock object created by SysRWLCreate

SysRWLReadUnlock (FUN) ¶ FUNCTION SysRWLReadUnlock : RTS_IEC_RESULT This function leaves a read lock, entered by SysRWLReadLock (synchronization object). RETURN: Returns the runtime system error code (see CmpErrors.library) InOut: Scope Name Type Comment Return SysRWLReadUnlock RTS_IEC_RESULT Input hRWLock RTS_IEC_HANDLE Handle to the ReadWrite lock object created by SysRWLCreate

SysRWLWriteLock (FUN) ¶ FUNCTION SysRWLWriteLock : RTS_IEC_RESULT This function to enter a write lock(synchronization object). NOTE: Several readers can enter the lock simultaneously! But they are synchronized against an entered write lock! RETURN: Returns the runtime system error code (see CmpErrors.library) InOut: Scope Name Type Comment Return SysRWLWriteLock RTS_IEC_RESULT Input hRWLock RTS_IEC_HANDLE Handle to the ReadWrite lock object created by SysRWLCreate

SysRWLWriteLockTry (FUN) ¶ FUNCTION SysRWLWriteLockTry : RTS_IEC_RESULT This function tries enter a write lock(synchronization object). If a write lock is still active, the functions returns an error. NOTE: Several readers can enter the lock simultaneously! But they are synchronized against an entered write lock! RETURN: Returns the runtime system error code (see CmpErrors.library) InOut: Scope Name Type Comment Return SysRWLWriteLockTry RTS_IEC_RESULT Input hRWLock RTS_IEC_HANDLE Handle to the ReadWrite lock object created by SysRWLCreate

SysRWLWriteUnlock (FUN) ¶ FUNCTION SysRWLWriteUnlock : RTS_IEC_RESULT This function leaves a write lock, entered by SysRWLReadLock (synchronization object). RETURN: Returns the runtime system error code (see CmpErrors.library) InOut: Scope Name Type Comment Return SysRWLWriteUnlock RTS_IEC_RESULT Input hRWLock RTS_IEC_HANDLE Handle to the ReadWrite lock object created by SysRWLCreate

SysSem Implementation Library Documentation ¶ Company System Title SysSem Implementation Version 3.5.17.0 Categories System|SysLibs Author CODESYS Development GmbH Placeholder SysSem Implementation Description 1 ¶ Library provides access to operating system semaphores on the runtime system for data synchronization. ATTENTION: Be aware, that a hangup could occur, if your task will be suspended because of a watchdog error in your protected code! Contents: ¶ SysSemCreate (Function) SysSemDelete (Function) SysSemEnter (Function) SysSemLeave (Function) SysSemTry (Function) Indices and tables ¶ 1 Based on SysSem Implementation.library, last modified 20.04.2021, 16:07:18. LibDoc 4.4.0.0-b.27 The content file SysSem Implementation.clean.json was generated with CODESYS V3.5 SP16 Patch 3 on 20.04.2021, 16:07:18.

SysSemCreate (FUN) ¶ FUNCTION SysSemCreate : RTS_IEC_HANDLE This function can be used to create a semaphore (synchronization object). InOut: Scope Name Type Comment Return SysSemCreate RTS_IEC_HANDLE Handle to the semaphore or RTS_INVALID_HANDLE if failed. Input pResult POINTER TO RTS_IEC_RESULT Pointer to runtime system error code (see CmpErrors.library)

SysSemDelete (FUN) ¶ FUNCTION SysSemDelete : RTS_IEC_RESULT This function deletes the semaphore which is identified by its handle. InOut: Scope Name Type Comment Return SysSemDelete RTS_IEC_RESULT Return the runtime system error code (see CmpErrors.library) Input hSem RTS_IEC_HANDLE Handle of the semaphore

SysSemEnter (FUN) ¶ FUNCTION SysSemEnter : RTS_IEC_RESULT This function must be called before a task accesses data which also are used by other tasks. Thus the data will be bocked for other tasks, which also use SysSemEnter until by function SysSemLeave the semaphore will be set free again. The semaphore is identified by its handle. InOut: Scope Name Type Comment Return SysSemEnter RTS_IEC_RESULT Returns the runtime system error code (see CmpErrors.library) Input hSem RTS_IEC_HANDLE Handle of the semaphore