NAME

       gethugepagesizes - Get the system supported huge page sizes

SYNOPSIS

       #include <hugetlbfs.h>

       int gethugepagesizes(long pagesizes[], int n_elem);

DESCRIPTION

       The  gethugepagesizes()  function  returns  either  the number of system supported huge page sizes or the
       sizes  themselves. If pagesizes is NULL and n_elem is 0,  then  the  number  of  huge  pages  the  system
       supports is returned. Otherwise, pagesizes is filled with at most n_elem page sizes.

RETURN VALUE

       On success, either the number of huge page sizes supported by the system or the number of huge page sizes
       stored in pagesizes is returned. On failure, -1 is returned and errno is set appropriately.

ERRORS

       EINVAL n_elem is less than zero or n_elem is greater than zero and pagesizes is NULL.

       Also see opendir(3) for other possible values for errno. This  error  occurs  when  the  sysfs  directory
       exists but cannot be opened.

NOTES

       This  call  will  return  all  huge  page sizes as reported by the kernel.  Not all of these sizes may be
       usable by the programmer since mount points may not be available for all sizes.  To test whether  a  size
       will be usable by libhugetlbfs, hugetlbfs_find_path_for_size() can be called on a specific size to see if
       a mount point is configured.

SEE ALSO

       oprofile(1), opendir(3), hugetlbfs_find_path_for_size(3), libhugetlbfs(7)

AUTHORS

       libhugetlbfs was written by various people on the libhugetlbfs-devel mailing list.

                                                October 10, 2008                             GETHUGEPAGESIZES(3)