munmap_flags()

Unmap previously mapped addresses, exercising more control than possible with munmap()

Synopsis:

#include <sys/mman.h>

int munmap_flags( void * addr,
                  size_t len,
                  unsigned flags );

Arguments:

addr: The beginning of the range of addresses that you want to unmap.
len: The length of the range of addresses, in bytes.
flags: There are no currently defined flags; pass 0 for this argument.

Library:

libc

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

Description:

The munmap_flags() function removes any mappings for pages in the address range starting at addr and continuing for len bytes, rounded up to the next multiple of the page size. Subsequent references to these pages cause a SIGSEGV signal to be set on the process.

If there are no mappings in the specified address range, then munmap_flags() has no effect.

Note: This function was added in the QNX Neutrino Core OS 6.3.2.

If you specify 0 for the flags, munmap_flags() is the same as munmap().

Returns:

0: Success.
-1: Failure; errno is set.

Errors:

EINVAL: The addresses in the specified range are outside the range allowed for the address space of a process.
ENOSYS: The function munmap_flags() isn't supported by this implementation.

Classification:

QNX Neutrino

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	Yes
Thread	Yes