freebsd man page for acl_add_perm

ACL_ADD_PERM(3) 					   BSD Library Functions Manual 					   ACL_ADD_PERM(3)

NAME
     acl_add_perm -- add permissions to a permission set

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <sys/types.h>
     #include <sys/acl.h>

     int
     acl_add_perm(acl_permset_t permset_d, acl_perm_t perm);

DESCRIPTION
     The acl_add_perm() function is a POSIX.1e call that adds the permission contained in perm to the permission set permset_d.

     Note: it is not considered an error to attempt to add permissions that already exist in the permission set.

     For POSIX.1e ACLs, valid values are:

	ACL_EXECUTE		 Execute permission
	ACL_WRITE		 Write permission
	ACL_READ		 Read permission

     For NFSv4 ACLs, valid values are:

	ACL_READ_DATA		 Read permission
	ACL_LIST_DIRECTORY	 Same as ACL_READ_DATA
	ACL_WRITE_DATA		 Write permission, or permission to create files
	ACL_ADD_FILE		 Same as ACL_READ_DATA
	ACL_APPEND_DATA 	 Permission to create directories.  Ignored for files
	ACL_ADD_SUBDIRECTORY	 Same as ACL_APPEND_DATA
	ACL_READ_NAMED_ATTRS	 Ignored
	ACL_WRITE_NAMED_ATTRS	 Ignored
	ACL_EXECUTE		 Execute permission
	ACL_DELETE_CHILD	 Permission to delete files and subdirectories
	ACL_READ_ATTRIBUTES	 Permission to read basic attributes
	ACL_WRITE_ATTRIBUTES	 Permission to change basic attributes
	ACL_DELETE		 Permission to delete the object this ACL is placed on
	ACL_READ_ACL		 Permission to read ACL
	ACL_WRITE_ACL		 Permission to change the ACL and file mode
	ACL_SYNCHRONIZE 	 Ignored

     Calling acl_add_perm() with perm equal to ACL_WRITE or ACL_READ brands the ACL as POSIX.  Calling it with ACL_READ_DATA, ACL_LIST_DIRECTORY,
     ACL_WRITE_DATA, ACL_ADD_FILE, ACL_APPEND_DATA, ACL_ADD_SUBDIRECTORY, ACL_READ_NAMED_ATTRS, ACL_WRITE_NAMED_ATTRS, ACL_DELETE_CHILD,
     ACL_READ_ATTRIBUTES, ACL_WRITE_ATTRIBUTES, ACL_DELETE, ACL_READ_ACL, ACL_WRITE_ACL or ACL_SYNCHRONIZE brands the ACL as NFSv4.

RETURN VALUES
     The acl_add_perm() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to
     indicate the error.

ERRORS
     The acl_add_perm() function fails if:

     [EINVAL]		Argument permset_d is not a valid descriptor for a permission set within an ACL entry.	Argument perm does not contain a
			valid acl_perm_t value.  ACL is already branded differently.

SEE ALSO
     acl(3), acl_clear_perms(3), acl_delete_perm(3), acl_get_brand_np(3), acl_get_permset(3), acl_set_permset(3), posix1e(3)

STANDARDS
     POSIX.1e is described in IEEE POSIX.1e draft 17.

HISTORY
     POSIX.1e support was introduced in FreeBSD 4.0.  The acl_add_perm() function was added in FreeBSD 5.0.

AUTHORS
     The acl_add_perm() function was written by Chris D. Faulhaber <jedgar@fxp.org>.

BSD
								   June 25, 2009							       BSD