remove a mapping
system call deletes the mappings for the specified address range, and causes
further references to addresses within the range to generate invalid memory
Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the error.
munmap() will fail if:
- The addr and len parameters specify a region that would extend beyond the end of the address space, or some part of the region being unmapped is not part of the currently valid address space.
madvise(2), mlock(2), mlockall(2), mmap(2), mprotect(2), msync(2), getpagesize(3)
When len is non-zero, the
munmap() function conforms to IEEE
Std 1003.1-2008 (“POSIX.1”).
munmap() system call has been
available since 4.3BSD-Net/2.
IEEE Std 1003.1-2008
(“POSIX.1”) specifies that
munmap() shall fail with
EINVAL if len is 0.
OpenBSD performs no action in this case.