The getpagesizes() function returns either the number of different page sizes supported by the system or the actual sizes themselves. When called with nelem as 0 and pagesize as NULL, getpagesizes() returns the number of supported page sizes. Otherwise, up to nelem page sizes are retrieved and assigned to successive elements of pagesize[]. The return value is the number of page sizes retrieved and set in pagesize[].

Upon successful completion, the number of pagesizes supported or actually retrieved is returned. Otherwise, -1 is returned and errno is set to indicate the error.

The getpagesizes() function will fail if:

EINVAL

The nelem argument is less than 0 or pagesize is NULL but nelem is non-zero.

The getpagesizes() function returns all the page sizes for which the hardware and system software provide support for the memcntl(2) command MC_HATMAPSIZE. However, not all processors support all page sizes and/or combinations of page sizes with equal efficiency. Applications programmers should take this into consideration when using getpagesizes().

See attributes(5) for descriptions of the following attributes:

memcntl(2), mmap(2), getpagesize(3C), attributes(5)