xref: /freebsd/lib/libc/posix1e/acl_get.3 (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
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30.Dd June 25, 2009
31.Dt ACL_GET 3
32.Os
33.Sh NAME
34.Nm acl_get_fd ,
35.Nm acl_get_fd_np ,
36.Nm acl_get_file ,
37.Nm acl_get_link_np
38.Nd get an ACL for a file
39.Sh LIBRARY
40.Lb libc
41.Sh SYNOPSIS
42.In sys/types.h
43.In sys/acl.h
44.Ft acl_t
45.Fn acl_get_fd "int fd"
46.Ft acl_t
47.Fn acl_get_fd_np "int fd" "acl_type_t type"
48.Ft acl_t
49.Fn acl_get_file "const char *path_p" "acl_type_t type"
50.Ft acl_t
51.Fn acl_get_link_np "const char *path_p" "acl_type_t type"
52.Sh DESCRIPTION
53The
54.Fn acl_get_fd ,
55.Fn acl_get_file ,
56.Fn acl_get_link_np ,
57and
58.Fn acl_get_fd_np
59each allow the retrieval of an ACL from a file.
60The
61.Fn acl_get_fd
62is a POSIX.1e call that allows the retrieval of an ACL of type
63ACL_TYPE_ACCESS
64from a file descriptor.
65The
66.Fn acl_get_fd_np
67function
68is a non-portable form of
69.Fn acl_get_fd
70that allows the retrieval of any type of ACL from a file descriptor.
71The
72.Fn acl_get_file
73function is a POSIX.1e call that allows the retrieval of a
74specified type of ACL from a file by name;
75.Fn acl_get_link_np
76is a non-portable variation on
77.Fn acl_get_file
78which does not follow a symlink if the target of the call is a
79symlink.
80.Pp
81These functions may cause memory to be allocated.
82The caller should free
83any releasable memory, when the new ACL is no longer required, by calling
84.Xr acl_free 3
85with the
86.Va (void *)acl_t
87as an argument.
88.Pp
89The ACL in the working storage is an independent copy of the ACL associated
90with the object referred to by
91.Va fd .
92The ACL in the working storage shall not participate in any access control
93decisions.
94.Pp
95Valid values for the
96.Va type
97argument are:
98.Bl -column -offset 3n "ACL_TYPE_DEFAULT"
99.It ACL_TYPE_ACCESS	POSIX.1e access ACL
100.It ACL_TYPE_DEFAULT	POSIX.1e default ACL
101.It ACL_TYPE_NFS4	NFSv4 ACL
102.El
103.Pp
104The ACL returned will be branded accordingly.
105.Sh IMPLEMENTATION NOTES
106.Fx Ns 's
107support for POSIX.1e interfaces and features is still under
108development at this time.
109.Sh RETURN VALUES
110Upon successful completion, the function shall return a pointer to the ACL
111that was retrieved.
112Otherwise, a value of
113.Va (acl_t)NULL
114shall be returned, and
115.Va errno
116shall be set to indicate the error.
117.Sh ERRORS
118If any of the following conditions occur, the
119.Fn acl_get_fd
120function shall return a value of
121.Va (acl_t)NULL
122and set
123.Va errno
124to the corresponding value:
125.Bl -tag -width Er
126.It Bq Er EACCES
127Search permission is denied for a component of the path prefix, or the
128object exists and the process does not have appropriate access rights.
129.It Bq Er EBADF
130The
131.Va fd
132argument is not a valid file descriptor.
133.It Bq Er EINVAL
134The ACL type passed is invalid for this file object.
135.It Bq Er ENAMETOOLONG
136A component of a pathname exceeded 255 characters, or an
137entire path name exceeded 1023 characters.
138.It Bq Er ENOENT
139The named object does not exist, or the
140.Va path_p
141argument points to an empty string.
142.It Bq Er ENOMEM
143Insufficient memory available to fulfill request.
144.It Bq Er EOPNOTSUPP
145The file system does not support ACL retrieval.
146.El
147.Sh SEE ALSO
148.Xr acl 3 ,
149.Xr acl_free 3 ,
150.Xr acl_get 3 ,
151.Xr acl_get_brand_np 3 ,
152.Xr acl_set 3 ,
153.Xr posix1e 3
154.Sh STANDARDS
155POSIX.1e is described in IEEE POSIX.1e draft 17.
156Discussion
157of the draft continues on the cross-platform POSIX.1e implementation
158mailing list.
159To join this list, see the
160.Fx
161POSIX.1e implementation
162page for more information.
163.Sh HISTORY
164POSIX.1e support was introduced in
165.Fx 4.0 ,
166and development continues.
167.Sh AUTHORS
168.An Robert N M Watson
169