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The <sys/mman.h> header shall be supported if the implementation supports at least one of the following options:

[MF] The Memory Mapped Files option
[SHM] The Shared Memory Objects option
[ML] The Process Memory Locking option
[MPR] The Memory Protection option
[TYM] The Typed Memory Objects option
[SIO] The Synchronized Input and Output option
[ADV] The Advisory Information option

[MC2] [Option Start] 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: [Option End]

PROT_READ

[MC2] [Option Start] Page can be read. [Option End]

PROT_WRITE

[MC2] [Option Start] Page can be written. [Option End]

PROT_EXEC

[MC2] [Option Start] Page can be executed. [Option End]

PROT_NONE

[MC2] [Option Start] Page cannot be accessed. [Option End]

The following flag options shall be defined:

MAP_SHARED

[MF|SHM] [Option Start] Share changes. [Option End]

MAP_PRIVATE

[MF|SHM] [Option Start] Changes are private. [Option End]

MAP_FIXED

[MF|SHM] [Option Start] Interpret addr exactly. [Option End]

The following flags shall be defined for msync():

MS_ASYNC

[MF|SIO] [Option Start] Perform asynchronous writes. [Option End]

MS_SYNC

[MF|SIO] [Option Start] Perform synchronous writes. [Option End]

MS_INVALIDATE

[MF|SIO] [Option Start] Invalidate mappings. [Option End]

[ML] [Option Start] The following symbolic constants shall be defined for the mlockall() function: [Option End]

MCL_CURRENT

[ML] [Option Start] Lock currently mapped pages. [Option End]

MCL_FUTURE

[ML] [Option Start] Lock pages that become mapped. [Option End]

[MF|SHM] [Option Start] The symbolic constant MAP_FAILED shall be defined to indicate a failure from the mmap() function. [Option End]

[MC1] [Option Start] 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

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_SEQUENTIAL

The application expects to access the specified range sequentially from lower addresses to higher addresses.

POSIX_MADV_RANDOM

The application expects to access the specified range in a random order.

POSIX_MADV_WILLNEED

The application expects to access the specified range in the near future.

POSIX_MADV_DONTNEED

The application expects that it will not access the specified range in the near future.

[Option End]

[TYM] [Option Start] The following flags shall be defined for posix_typed_mem_open():

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.

[Option End]

The mode_t, off_t, and size_t types shall be defined as described in <sys/types.h>.

[TYM] [Option Start] 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.

[Option End]

The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided.

[MLR] [Option Start] int mlock(const void *, size_t); [Option End] [ML] int mlockall(int); [MC3] void *mmap(void *, size_t, int, int, int, off_t); [MPR] int mprotect(void *, size_t, int); [MF|SIO] int msync(void *, size_t, int); [MLR] int munlock(const void *, size_t); [ML] int munlockall(void); [MC3] [Option Start] int munmap(void *, size_t); [Option End] [ADV] int posix_madvise(void *, size_t, int); [TYM] 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); [Option End] [SHM] [Option Start] int shm_open(const char *, int, mode_t); int shm_unlink(const char *);

The following sections are informative.

The <sys/mman.h> header is marked as dependent on support for either the Memory Mapped Files, Process Memory Locking, or Shared Memory Objects options.

The following changes are made for alignment with IEEE Std 1003.1j-2000:

The TYM margin code is added to the list of margin codes for the <sys/mman.h> header line, as well as for other lines.
The POSIX_TYPED_MEM_ALLOCATE, POSIX_TYPED_MEM_ALLOCATE_CONTIG, and POSIX_TYPED_MEM_MAP_ALLOCATABLE flags are added.
The posix_tmi_length structure is added.
The posix_mem_offset(), posix_typed_mem_get_info(), and posix_typed_mem_open() functions are added.

The restrict keyword is added to the prototype for posix_mem_offset().

IEEE PASC Interpretation 1003.1 #102 is applied, adding the prototype for posix_madvise().

IEEE Std 1003.1-2001/Cor 1-2002, item XBD/TC1/D6/16 is applied, correcting margin code and shading errors for the mlock() and munlock() functions.

IEEE Std 1003.1-2001/Cor 1-2002, item XSH/TC1/D6/34 is applied, changing the margin code for the mmap() function from MF|SHM to MC3 (notation for MF|SHM|TYM).

IEEE Std 1003.1-2001/Cor 1-2002, item XSH/TC1/D6/36 is applied, changing the margin code for the munmap() function from MF|SHM to MC3 (notation for MF|SHM|TYM).

End of informative text.