MUNMAP(2) System Calls MUNMAP(2)
munmap - unmap pages of memory
#include <sys/mman.h>
int munmap(void *addr, size_t len);
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().
Upon successful completion, munmap() returns 0; otherwise, it returns
-1 and sets errno to indicate an error.
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.
See attributes(7) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+
mmap(2), sysconf(3C), attributes(7), standards(7)
January 5, 1998 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(7) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+
SEE ALSO
mmap(2), sysconf(3C), attributes(7), standards(7)
January 5, 1998 MUNMAP(2)