freebsd-skq/lib/libposix1e/acl_from_text.3

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.Dd January 28, 2000
.Dt ACL_FROM_TEXT 3
.Os FreeBSD 4.0
.Sh NAME
.Nm acl_from_text
.Nd Create an ACL from text
.Sh SYNOPSIS
.Fd #include <sys/types.h>
.Fd #include <sys/acl.h>
.Ft acl_t
.Fn acl_from_text "const char *buf_p"
.Sh DESCRIPTION
The
.Fn acl_from_text
function converts the text form of an ACL referred to by
.Va buf_p
into the internal working structure for ACLs, appropriate for applying to
files or manipulating.

This function may cause memory to be allocated.  The caller should free any
releasable memory, when the new ACL is no longer required, by calling
.Xr acl_free 3
with the
.Va (void *)acl_t
as an argument.
.Sh IMPLEMENTATION NOTES
FreeBSD's support for POSIX.1e interfaces and features is still under
development at this time.
.Sh RETURN VALUES
Upon successful completion, the function shall return a pointer to the
internal representation of the ACL in working storage.  Otherwise, a value
of
.Va (acl_t)NULL
shall be returned, and
.Va errno
shall be set to indicate the error.
.Sh ERRORS
If any of the following conditions occur, the
.Fn acl_from_text
function shall return a value of
.Va (acl_t)NULL
and set
.Va errno
to the corresponding value:
.Bl -tag -width Er
.It Bq Er EACCES
Search permission is denied for a component of the path prefix, or the
object exists and the process does not have appropriate access rights.
.It Bq Er EINVAL
Argument
.Va buf_p
cannot be translated into an ACL.
.It Bq Er ENOMEM
The ACL working storage requires more memory than is allowed by the
hardware or system-imposed memory management constraints.
.El
.Sh SEE ALSO
.Xr acl 3 ,
.Xr acl_free 3 ,
.Xr acl_get 3 ,
.Xr acl_to_text 3 ,
.Xr posix1e 3
.Sh STANDARDS
POSIX.1e is described in IEEE POSIX.1e draft 17.  Discussion
of the draft continues on the cross-platform POSIX.1e implementation
mailing list.  To join this list, see the
.Fx
POSIX.1e implementation
page for more information.
.Sh HISTORY
POSIX.1e support was introduced in
.Fx 4.0 ,
and development continues.
.Sh AUTHORS
.An Robert N M Watson
.Sh BUGS
These features are not yet fully implemented.  In particular, the shipped
version of UFS/FFS does not support storage of additional security labels,
and so is unable to (easily) provide support for most of these features.

.Fn acl_from_text
and
.Fn acl_to_text
rely on the
.Xr getpwent 3
library calls to manage username and uid mapping, as well as the
.Xr getgrent 3
library calls to manage groupname and gid mapping.  These calls are not
thread safe, and so transitively, neither are 
.Fn acl_from_text
and
.Fn acl_to_text .
These functions may also interfere with stateful
calls associated with the 
.Fn getpwent
and
.Fn getgrent
calls.