mmap.2 (2010 09)

m
mmap(2) mmap(2)
support fine-grained privileges.
RETURN VALUE
Upon successful completion,
mmap() returns the address, (pa), at which the mapping was placed. Oth-
erwise, it returns
MAP_FAILED (defined in
<sys/mman.h>) and sets errno to indicate the error.
ERRORS
The
mmap() function will fail if:
[EBADF] The fildes argument is not a valid open file descriptor.
[EACCES] The fildes argument is not open for read, regardless of the protection specified, or
fildes is not open for write and
PROT_WRITE was specified for a MAP_SHARED type
mapping.
[ENXIO] Addresses in the range [off, off+len] are invalid for fildes .
[ENXIO]
MAP_FIXED was specified in flags and the combination of addr, len , and off is
invalid for the object specified by fildes .
[EINVAL] The addr argument (if
MAP_FIXED was specified) or off is not a multiple of the
page size as returned by
sysconf(), or are considered invalid by the implementa-
tion.
[EINVAL] The value of flags is invalid (neither
MAP_PRIVATE
nor MAP_SHARED is set).
[EINVAL] The mapping already exists in 64-bit address space, but the application performing
the current
mmap() request has been compiled as a 32-bit executable.
[EINVAL] The mapping already exists in 32-bit address space, but the application performing
the current
mmap() request has been compiled as a 64-bit executable and did not
specify MAP_ADDR32 in the flags argument.
[EINVAL] The value of off+len exceeds the maximum supported offset for mapped files.
[EINVAL] The mapping request used the
MAP_IO flag and the requested range is not a valid
range of I/O memory, the requested range is already mapped as restricted to kernel
usage, or the mapping is for an address range which overlaps but is not equal to an
existing mapping.
[EMFILE] The number of mapped regions would exceed an implementation-dependent limit
(per process or per system).
[ENODEV] The fildes argument refers to a file whose type is not supported by
mmap().
[ENOMEM]
MAP_FIXED was specified, and the range [addr, addr+len] exceeds that allowed
for the address space of a process. Or, MAP_FIXED was not specified and there is
insufficient room in the address space to effect the mapping.
[EOVERFLOW]
The file is a regular file and the value of off+len exceeds the offset maximum esta-
blished in the open file description associated with fildes .
[EPERM] The mapping request used the
MAP_IO flag and the calling process does not have
the DEVOPS privilege and is not a Real Time process.
[ETXTBSY]
MAP_SHARED and MAP_FILE are set, and PROT_EXECUTE is set and
PROT_WRITE is not set, and the file being mapped is currently open for writing.
DEPENDENCIES
PA-RISC Architecture
Because the PA-RISC memory architecture utilizes a globally shared virtual address space between
processes and discourages multiple virtual address translations to the same physical address, all con-
currently existing
MAP_SHARED mappings of a file range must share the same virtual address offsets and
hardware translations. PA-RISC-based HP-UX systems allocate virtual address ranges for shared
memory and shared mapped files in the range 0x80000000 through 0xefffffff for those applica-
tions compiled as 32-bit executables or for those 64-bit applications which specify MAP_SHARED and
MAP_ADDR32 in the flags argument of the mmap() function. For applications compiled as 64-bit execut-
ables which specify MAP_SHARED and do not specify MAP_ADDR32, the shared mapped files are in the
range 0x00000011 00000000 through 0x000003ff ffffffff and 0xc0000000 00000000
through 0xc00003ff ffffffff. These address ranges are used globally for all memory objects
HP-UX 11i Version 3: September 2010 − 5 − Hewlett-Packard Company 5