декларации управления памятью (memory management declarations)
Пролог (Prolog)
This manual page is part of the POSIX Programmer's Manual. The
Linux implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
Имя (Name)
sys/mman.h — memory management declarations
Синопсис (Synopsis)
#include <sys/mman.h>
Описание (Description)
The <sys/mman.h> header shall define the following symbolic
constants for use as protection options:
PROT_EXEC Page can be executed.
PROT_NONE Page cannot be accessed.
PROT_READ Page can be read.
PROT_WRITE Page can be written.
The <sys/mman.h> header shall define the following symbolic
constants for use as flag options:
MAP_FIXED Interpret addr exactly.
MAP_PRIVATE Changes are private.
MAP_SHARED Share changes.
The <sys/mman.h> header shall define the following symbolic
constants for the msync() function:
MS_ASYNC Perform asynchronous writes.
MS_INVALIDATE Invalidate mappings.
MS_SYNC Perform synchronous writes.
The <sys/mman.h> header shall define the following symbolic
constants for the mlockall() function:
MCL_CURRENT Lock currently mapped pages.
MCL_FUTURE Lock pages that become mapped.
The <sys/mman.h> header shall define the symbolic constant
MAP_FAILED which shall have type void * and shall be used to
indicate a failure from the mmap() function .
If the Advisory Information option is supported, the <sys/mman.h>
header shall define symbolic constants for the advice argument to
the posix_madvise() function as follows:
POSIX_MADV_DONTNEED
The application expects that it will not access the
specified range in the near future.
POSIX_MADV_NORMAL
The application has no advice to give on its behavior with
respect to the specified range. It is the default
characteristic if no advice is given for a range of memory.
POSIX_MADV_RANDOM
The application expects to access the specified range in a
random order.
POSIX_MADV_SEQUENTIAL
The application expects to access the specified range
sequentially from lower addresses to higher addresses.
POSIX_MADV_WILLNEED
The application expects to access the specified range in
the near future.
The <sys/mman.h> header shall define the following symbolic
constants for use as flags for the posix_typed_mem_open()
function:
POSIX_TYPED_MEM_ALLOCATE
Allocate on mmap().
POSIX_TYPED_MEM_ALLOCATE_CONTIG
Allocate contiguously on mmap().
POSIX_TYPED_MEM_MAP_ALLOCATABLE
Map on mmap(), without affecting allocatability.
The <sys/mman.h> header shall define the mode_t, off_t, and
size_t types as described in sys_types.h(0p).
The <sys/mman.h> header shall define the posix_typed_mem_info
structure, which shall include at least the following member:
size_t posix_tmi_length Maximum length which may be allocated
from a typed memory object.
The following shall be declared as functions and may also be
defined as macros. Function prototypes shall be provided.
int mlock(const void *, size_t);
int mlockall(int);
void *mmap(void *, size_t, int, int, int, off_t);
int mprotect(void *, size_t, int);
int msync(void *, size_t, int);
int munlock(const void *, size_t);
int munlockall(void);
int munmap(void *, size_t);
int posix_madvise(void *, size_t, int);
int posix_mem_offset(const void *restrict, size_t, off_t *restrict,
size_t *restrict, int *restrict);
int posix_typed_mem_get_info(int, struct posix_typed_mem_info *);
int posix_typed_mem_open(const char *, int, int);
int shm_open(const char *, int, mode_t);
int shm_unlink(const char *);
The following sections are informative.
Использование в приложениях (Application usage)
None.
Обоснование (Rationale)
None.
Будущие направления (Future directions)
None.
Смотри также (See also)
sys_types.h(0p)
The System Interfaces volume of POSIX.1‐2017, mlock(3p),
mlockall(3p), mmap(3p), mprotect(3p), msync(3p), munmap(3p),
posix_madvise(3p), posix_mem_offset(3p),
posix_typed_mem_get_info(3p), posix_typed_mem_open(3p),
shm_open(3p), shm_unlink(3p)
