acl_get_tag_type —
retrieve the tag type from an ACL entry
Standard C Library (libc, -lc)
#include <sys/types.h>
#include <sys/acl.h>
int
  
  acl_get_tag_type(acl_entry_t
    entry_d, acl_tag_t
    *tag_type_p);
The acl_get_tag_type() function is a POSIX.1e call that
  returns the tag type for the ACL entry entry_d. Upon
  successful completion, the location referred to by the argument
  tag_type_p will be set to the tag type of the ACL entry
  entry_d.
The acl_get_tag_type() function returns the
  value 0 if successful; otherwise the value -1 is returned and
  the global variable errno is set to indicate the error.
The acl_get_tag_type() function fails if:
  - [EINVAL]
- Argument entry_d is not a valid descriptor for an
      ACL entry;
POSIX.1e is described in IEEE POSIX.1e draft 17.
POSIX.1e support was introduced in FreeBSD 4.0. Theacl_get_tag_type() function was added in
  FreeBSD 5.0.
The acl_get_tag_type() function was written by
  Chris D. Faulhaber
  <jedgar@fxp.org>.