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QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
Utilities & Libraries
C Library Reference
I
InterruptUnlock()
Unlock a spinlock and re-enable interrupts

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        Unlock the attribute structure
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        Unblock OCBs
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        Default unblock handler
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        Verify that an entry can be unlinked
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        Default handler for the unlock_ocb callout
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InterruptUnlock()

QNX SDP8.0C Library ReferenceAPIDeveloper

Unlock a spinlock and re-enable interrupts

Synopsis:

#include <sys/neutrino.h>

void InterruptUnlock( intrspin_t* spinlock );

Arguments:

spinlock: The spinlock used in a call to InterruptLock().

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The InterruptUnlock() function releases a critical section by unlocking the specified spinlock, reenabling interrupts.

Before calling this function:

The process must have the PROCMGR_AID_IO ability enabled. For more information, see procmgr_ability().
The calling thread must have obtained I/O privileges by calling:
```
ThreadCtl( _NTO_TCTL_IO_LEVEL, (void*)_NTO_IO_LEVEL_1 );
```

If you don't do these things, the thread might SIGSEGV when it calls InterruptUnlock().

Note:

This function doesn't support nesting. If a specific thread calls InterruptLock() multiple times with different spinlocks and then calls InterruptUnlock() the same number of times and in reverse order with the locks, the first InterruptUnlock() call reenables interrupts and the critical section is no longer protected.

Classification:


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 09, 2024