acl_get_perm_np —
check if a permission is set in a permission set
Standard C Library (libc, -lc)
#include <sys/types.h>
#include <sys/acl.h>
int
  
  acl_get_perm_np(acl_permset_t
    permset_d, acl_perm_t
    perm);
The acl_get_perm_np() function is a non-portable
  function that checks if a permission is set in a permission set.
If the permission in perm is set in the permission set
  permset_d, a value of 1 is returned, otherwise a value
  of 0 is returned.
If any of the following conditions occur, the
  acl_get_perm_np() function will return a value of -1
  and set global variable errno to the corresponding
  value:
  - [EINVAL]
- Argument perm does not contain a valid ACL
      permission or argument permset_d is not a valid ACL
      permset.
POSIX.1e is described in IEEE POSIX.1e draft 17.
POSIX.1e support was introduced in FreeBSD 4.0. Theacl_get_perm_np() function was added in
  FreeBSD 5.0.
The acl_get_perm_np() function was written by
  Chris D. Faulhaber
  <jedgar@fxp.org>.