Linux Access Control Lists library (libacl, -lacl).  The function
deletes   the  permission  contained  in  the  argument  (one  of
ACL_READ, ACL_WRITE, ACL_EXECUTE) from  the  permission  set  re‐
ferred  to by the argument An attempt to delete a permission that
is not contained in the permission set is not considered  an  er‐
ror.  Any existing descriptors that refer to continue to refer to
that  permission  set.  If any of the following conditions occur,
the function returns and sets to the corresponding value: The ar‐
gument is not a valid descriptor for a permission set  within  an
ACL  entry.   The  argument does not contain a valid value.  IEEE
Std 1003.1e draft 17 (“POSIX.1e”,  abandoned)  Derived  from  the
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