munmap.2 (2010 09)

munmap(2) 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().Ifaddr is not the

address of a mapping established by a prior call to

mmap(), 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.

If the speciﬁed address range was created by multiple calls to

mmap(), munmap() succeeds in unmap-

ping all of the speciﬁed regions, provided they form a contiguous address range.

If the region was created with the

MAP_PRIVATE

option, any modiﬁcations made to the region are dis-

carded.

RETURN VALUE

Upon successful completion,

munmap() returns 0. Otherwise, it returns − 1 and sets errno to indicate

the error.

ERRORS

The

munmap() function will fails if:

[EINVAL] The addr argument is not a multiple of the page size as returned by

sysconf(_SC_PAGE_SIZE)

[EINVAL] Addresses in the range [addr , addr +len ], are outside the valid range for the

address space of a process.

[EINVAL] The address range speciﬁed by addr and len was not created by a successful call to

mmap().

[EINVAL] The len argument is

AUTHOR

munmap() was developed by HP, AT&T, and OSF.

PAGE 1
munmap(2) munmap(2) NAME munmap - unmap pages of memory SYNOPSIS #include 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(). If addr is not the address of a mapping established by a prior call to mmap(), the behavior is undefined.
PAGE 2
(Notes) A (Notes) mA 2 Hewlett-Packard Company −1− HP-UX 11i Version 3: September 2010