xref: /freebsd/lib/libc/posix1e/acl_to_text.3 (revision 38f1b189cd839bd8aa122ae06cc084810ca1e395)
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30.Dd June 25, 2009
31.Dt ACL_TO_TEXT 3
32.Os
33.Sh NAME
34.Nm acl_to_text ,
35.Nm acl_to_text_np
36.Nd convert an ACL to text
37.Sh LIBRARY
38.Lb libc
39.Sh SYNOPSIS
40.In sys/types.h
41.In sys/acl.h
42.Ft char *
43.Fn acl_to_text "acl_t acl" "ssize_t *len_p"
44.Ft char *
45.Fn acl_to_text_np "acl_t acl" "ssize_t *len_p" "int flags"
46.Sh DESCRIPTION
47The
48.Fn acl_to_text
49and
50.Fn acl_to_text_np
51functions translate the ACL pointed to by argument
52.Va acl
53into a NULL terminated character string.
54If the pointer
55.Va len_p
56is not NULL, then the function shall return the length of the string (not
57including the NULL terminator) in the location pointed to by
58.Va len_p .
59If the ACL is POSIX.1e, the format of the text string returned by
60.Fn acl_to_text
61shall be the POSIX.1e long ACL form.  If the ACL is NFSv4, the format
62of the text string shall be the compact form, unless the
63.Va ACL_TEXT_VERBOSE
64flag is given.
65.Pp
66The flags specified are formed by
67.Em or Ns 'ing
68the following values
69.Bl -column -offset 3n "ACL_TEXT_NUMERIC_IDS"
70.It ACL_TEXT_VERBOSE Ta "Format ACL using verbose form"
71.It ACL_TEXT_NUMERIC_IDS Ta "Do not resolve IDs into user or group names"
72.It ACL_TEXT_APPEND_ID Ta "In addition to user and group names, append numeric IDs"
73.El
74.Pp
75This function allocates any memory necessary to contain the string and
76returns a pointer to the string.
77The caller should free any releasable
78memory, when the new string is no longer required, by calling
79.Xr acl_free 3
80with the
81.Va (void*)char
82as an argument.
83.Sh IMPLEMENTATION NOTES
84.Fx Ns 's
85support for POSIX.1e interfaces and features is still under
86development at this time.
87.Sh RETURN VALUES
88Upon successful completion, the function shall return a pointer to the
89long text form of an ACL.
90Otherwise, a value of
91.Va (char*)NULL
92shall be returned and
93.Va errno
94shall be set to indicate the error.
95.Sh ERRORS
96If any of the following conditions occur, the
97.Fn acl_to_text
98function shall return a value of
99.Va (acl_t)NULL
100and set
101.Va errno
102to the corresponding value:
103.Bl -tag -width Er
104.It Bq Er EINVAL
105Argument
106.Va acl
107does not point to a valid ACL.
108.Pp
109The ACL denoted by
110.Va acl
111contains one or more improperly formed ACL entries, or for some other
112reason cannot be translated into a text form of an ACL.
113.It Bq Er ENOMEM
114The character string to be returned requires more memory than is allowed
115by the hardware or software-imposed memory management constraints.
116.El
117.Sh SEE ALSO
118.Xr acl 3 ,
119.Xr acl_free 3 ,
120.Xr acl_from_text 3 ,
121.Xr posix1e 3
122.Sh STANDARDS
123POSIX.1e is described in IEEE POSIX.1e draft 17.
124Discussion
125of the draft continues on the cross-platform POSIX.1e implementation
126mailing list.
127To join this list, see the
128.Fx
129POSIX.1e implementation
130page for more information.
131.Sh HISTORY
132POSIX.1e support was introduced in
133.Fx 4.0 ,
134and development continues.
135.Sh AUTHORS
136.An Robert N M Watson
137.Sh BUGS
138The
139.Fn acl_from_text
140and
141.Fn acl_to_text
142functions
143rely on the
144.Xr getpwent 3
145library calls to manage username and uid mapping, as well as the
146.Xr getgrent 3
147library calls to manage groupname and gid mapping.
148These calls are not
149thread safe, and so transitively, neither are
150.Fn acl_from_text
151and
152.Fn acl_to_text .
153These functions may also interfere with stateful
154calls associated with the
155.Fn getpwent
156and
157.Fn getgrent
158calls.
159