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SunOS man pages : 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 esta- blished by a prior call to mmap(2), the behavior is unde- fined. 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.

SEE ALSO

mmap(2), sysconf(3C) SunOS 5.8 Last change: 5 Jan 1998 1