<sys/mman.h>(0P) | POSIX Programmer's Manual | <sys/mman.h>(0P) |
NAME
sys/mman.h - memory management declarationsSYNOPSIS
#include <sys/mman.h>DESCRIPTION
The <sys/mman.h> header shall be supported if the implementation supports at least one of the following options:- *
- The Memory Mapped Files option
- *
- The Shared Memory Objects option
- *
- The Process Memory Locking option
- *
- The Memory Protection option
- *
- The Typed Memory Objects option
- *
- The Synchronized Input and Output option
- *
- The Advisory Information option
- *
- The Typed Memory Objects option
If one or more of the Advisory Information, Memory Mapped Files, or Shared Memory Objects options are supported, the following protection options shall be defined:
- PROT_READ
- Page can be read.
- PROT_WRITE
- Page can be written.
- PROT_EXEC
- Page can be executed.
- PROT_NONE
-
Page cannot be accessed.
The following flag options shall be defined:
- MAP_SHARED
- Share changes.
- MAP_PRIVATE
- Changes are private.
- MAP_FIXED
-
Interpret
addr exactly.
The following flags shall be defined for msync():
- MS_ASYNC
- Perform asynchronous writes.
- MS_SYNC
- Perform synchronous writes.
- MS_INVALIDATE
-
Invalidate mappings.
The following symbolic constants shall be defined for the mlockall() function:
- MCL_CURRENT
- Lock currently mapped pages.
- MCL_FUTURE
-
Lock pages that become mapped.
The symbolic constant MAP_FAILED shall be defined to indicate a failure from the mmap() function.
If the Advisory Information and either the Memory Mapped Files or Shared Memory Objects options are supported, values for advice used by posix_madvise() shall be defined as follows:
- POSIX_MADV_NORMAL
-
- POSIX_MADV_SEQUENTIAL
-
- POSIX_MADV_RANDOM
-
- POSIX_MADV_WILLNEED
-
- POSIX_MADV_DONTNEED
-
The following flags shall be defined for posix_typed_mem_open():
- POSIX_TYPED_MEM_ALLOCATE
-
- POSIX_TYPED_MEM_ALLOCATE_CONTIG
-
- POSIX_TYPED_MEM_MAP_ALLOCATABLE
-
The mode_t, off_t, and size_t types shall be defined as described in <sys/types.h> .
The <sys/mman.h> header shall define the structure posix_typed_mem_info, which includes 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.
APPLICATION USAGE
None.RATIONALE
None.FUTURE DIRECTIONS
None.SEE ALSO
<sys/types.h>, the System Interfaces volume of IEEE Std 1003.1-2001, mlock(), mlockall(), mmap(), mprotect(), msync(), munlock(), munlockall(), munmap(), posix_mem_offset(), posix_typed_mem_get_info(), posix_typed_mem_open(), shm_open(), shm_unlink()COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .2003 | IEEE/The Open Group |