xref: /netbsd-src/lib/libc/posix1e/acl_get.3 (revision 1b3734281f17fd86d3db0e29f84ea9985be6fe06)
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29.\" $FreeBSD: head/lib/libc/posix1e/acl_get.3 213573 2010-10-08 12:40:16Z uqs $
30.\"
31.Dd June 25, 2009
32.Dt ACL_GET 3
33.Os
34.Sh NAME
35.Nm acl_get_fd ,
36.Nm acl_get_fd_np ,
37.Nm acl_get_file ,
38.Nm acl_get_link_np
39.Nd get an ACL for a file
40.Sh LIBRARY
41.Lb libc
42.Sh SYNOPSIS
43.In sys/types.h
44.In sys/acl.h
45.Ft acl_t
46.Fn acl_get_fd "int fd"
47.Ft acl_t
48.Fn acl_get_fd_np "int fd" "acl_type_t type"
49.Ft acl_t
50.Fn acl_get_file "const char *path_p" "acl_type_t type"
51.Ft acl_t
52.Fn acl_get_link_np "const char *path_p" "acl_type_t type"
53.Sh DESCRIPTION
54The
55.Fn acl_get_fd ,
56.Fn acl_get_file ,
57.Fn acl_get_link_np ,
58and
59.Fn acl_get_fd_np
60each allow the retrieval of an ACL from a file.
61The
62.Fn acl_get_fd
63is a POSIX.1e call that allows the retrieval of an ACL of type
64ACL_TYPE_ACCESS
65from a file descriptor.
66The
67.Fn acl_get_fd_np
68function
69is a non-portable form of
70.Fn acl_get_fd
71that allows the retrieval of any type of ACL from a file descriptor.
72The
73.Fn acl_get_file
74function is a POSIX.1e call that allows the retrieval of a
75specified type of ACL from a file by name;
76.Fn acl_get_link_np
77is a non-portable variation on
78.Fn acl_get_file
79which does not follow a symlink if the target of the call is a
80symlink.
81.Pp
82These functions may cause memory to be allocated.
83The caller should free
84any releasable memory, when the new ACL is no longer required, by calling
85.Xr acl_free 3
86with the
87.Va (void *)acl_t
88as an argument.
89.Pp
90The ACL in the working storage is an independent copy of the ACL associated
91with the object referred to by
92.Va fd .
93The ACL in the working storage shall not participate in any access control
94decisions.
95.Pp
96Valid values for the
97.Va type
98argument are:
99.Bl -column -offset 3n "ACL_TYPE_DEFAULT"
100.It ACL_TYPE_ACCESS	POSIX.1e access ACL
101.It ACL_TYPE_DEFAULT	POSIX.1e default ACL
102.It ACL_TYPE_NFS4	NFSv4 ACL
103.El
104.Pp
105The ACL returned will be branded accordingly.
106.Sh IMPLEMENTATION NOTES
107.Fx Ns 's
108support for POSIX.1e interfaces and features is still under
109development at this time.
110.Sh RETURN VALUES
111Upon successful completion, the function shall return a pointer to the ACL
112that was retrieved.
113Otherwise, a value of
114.Va (acl_t)NULL
115shall be returned, and
116.Va errno
117shall be set to indicate the error.
118.Sh ERRORS
119If any of the following conditions occur, the
120.Fn acl_get_fd
121function shall return a value of
122.Va (acl_t)NULL
123and set
124.Va errno
125to the corresponding value:
126.Bl -tag -width Er
127.It Bq Er EACCES
128Search permission is denied for a component of the path prefix, or the
129object exists and the process does not have appropriate access rights.
130.It Bq Er EBADF
131The
132.Va fd
133argument is not a valid file descriptor.
134.It Bq Er EINVAL
135The ACL type passed is invalid for this file object.
136.It Bq Er ENAMETOOLONG
137A component of a pathname exceeded 255 characters, or an
138entire path name exceeded 1023 characters.
139.It Bq Er ENOENT
140The named object does not exist, or the
141.Va path_p
142argument points to an empty string.
143.It Bq Er ENOMEM
144Insufficient memory available to fulfill request.
145.It Bq Er EOPNOTSUPP
146The file system does not support ACL retrieval.
147.El
148.Sh SEE ALSO
149.Xr acl 3 ,
150.Xr acl_free 3 ,
151.Xr acl_get 3 ,
152.Xr acl_get_brand_np 3 ,
153.Xr acl_set 3 ,
154.Xr posix1e 3
155.Sh STANDARDS
156POSIX.1e is described in IEEE POSIX.1e draft 17.
157Discussion
158of the draft continues on the cross-platform POSIX.1e implementation
159mailing list.
160To join this list, see the
161.Fx
162POSIX.1e implementation
163page for more information.
164.Sh HISTORY
165POSIX.1e support was introduced in
166.Fx 4.0 ,
167and development continues.
168.Sh AUTHORS
169.An Robert N M Watson
170