Linux Access Control Lists library (libacl, -lacl).  The function
translates  the  ACL pointed to by the argument into a terminated
character string. This character string is composed  of  the  ACL
entries  contained  in  in the entry text format described on En‐
tries are separated from each other by the character. If the  ar‐
gument  is  not  each entry is prefixed by this character string.
If the argument is ACL entries are converted using the entry  tag
type keywords and User IDs and group IDs of ACL entries that con‐
tain  such qualifiers are converted to their corresponding names;
if an identifier has no  corresponding  name,  a  decimal  number
string is produced. The ACL text representation contains no addi‐
tional  comments.  A bitwise combinations of the following can be
used to modify the result: Instead of the full tag type keywords,
single letter abbreviations are used.  The  abbreviation  for  is
the abbreviation for is the abbreviation for is and the abbrevia‐
tion  for  is User IDs and group IDs are included as decimal num‐
bers instead of names.  A comment containing the  effective  per‐
missions of the ACL entry is included after ACL entries that con‐
tain permissions which are ineffective because they are masked by
an ACL_MASK entry. The ACL entry and the comment are separated by
a  tab character.  A comment containing the effective permissions
of the ACL entry is included after all ACL entries that  are  af‐
fected by an ACL_MASK entry.  The comment is included even if the
permissions  contained  in the ACL entry equal the effective per‐
missions. The ACL entry and the comment are separated  by  a  tab
character.    This   option  is  used  in  combination  with  the
TEXT_SOME_EFFECTIVE or TEXT_ALL_EFFECTIVE option. The  number  of
tab  characters inserted between the ACL entry and the comment is
increased so that the comment is aligned to the fourth  tab  stop
position.   A  tab width of 8 characters is assumed.  The ACL re‐
ferred to by is not changed.  This function allocates any  memory
necessary  to  contain  the  string  and returns a pointer to the
string.  The caller should free any releasable memory,  when  the
new string is no longer required, by calling with the returned by
as  an  argument.  On success, this function returns a pointer to
the text representation of the ACL.  On error, a value of is  re‐
turned, and is set appropriately.  If any of the following condi‐
tions occur, the function returns a value of and sets to the cor‐
responding  value: The argument is not a valid pointer to an ACL.
The ACL referenced by contains one or more improperly formed  ACL
entries,  or  for some other reason cannot be translated into the
text form of an ACL.  The character string  to  be  returned  re‐
quires  more memory than is allowed by the hardware or system‐im‐
posed memory management constraints.   This  is  a  non‐portable,
Linux  specific  extension  to the ACL manipulation functions de‐
fined in IEEE  Std  1003.1e  draft  17  (“POSIX.1e”,  abandoned).
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