MUNMAP(2) System Calls MUNMAP(2)


NAME


munmap - unmap pages of memory

SYNOPSIS


#include <sys/mman.h>

int munmap(void *addr, size_t len);


DESCRIPTION


The munmap() function removes the mappings for pages in the range [addr,
addr + len), rounding the len argument up to the next multiple of the
page size as returned by sysconf(3C). If addr is not the address of a
mapping established by a prior call to mmap(2), the behavior is
undefined. After a successful call to munmap() and before any subsequent
mapping of the unmapped pages, further references to these pages will
result in the delivery of a SIGBUS or SIGSEGV signal to the process.


The mmap(2) function often performs an implicit munmap().

RETURN VALUES


Upon successful completion, munmap() returns 0; otherwise, it returns -1
and sets errno to indicate an error.

ERRORS


The munmap() function will fail if:

EINVAL
The addr argument is not a multiple of the page size as
returned by sysconf(3C); addresses in the range [addr, addr +
len) are outside the valid range for the address space of a
process; or the len argument has a value less than or equal to
0.


ATTRIBUTES


See attributes(5) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+

SEE ALSO


mmap(2), sysconf(3C), attributes(5), standards(5)


January 5, 1998 MUNMAP(2)