mirror of
https://github.com/python/cpython.git
synced 2025-11-04 03:44:55 +00:00
132 lines
3.6 KiB
TeX
132 lines
3.6 KiB
TeX
\chapter{Amoeba Specific Services}
|
|
|
|
\section{\module{amoeba} ---
|
|
Amoeba system support}
|
|
|
|
\declaremodule{builtin}{amoeba}
|
|
\platform{Amoeba}
|
|
\modulesynopsis{Functions for the Amoeba operating system.}
|
|
|
|
|
|
This module provides some object types and operations useful for
|
|
Amoeba applications. It is only available on systems that support
|
|
Amoeba operations. RPC errors and other Amoeba errors are reported as
|
|
the exception \code{amoeba.error = 'amoeba.error'}.
|
|
|
|
The module \module{amoeba} defines the following items:
|
|
|
|
\begin{funcdesc}{name_append}{path, cap}
|
|
Stores a capability in the Amoeba directory tree.
|
|
Arguments are the pathname (a string) and the capability (a capability
|
|
object as returned by
|
|
\function{name_lookup()}).
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{name_delete}{path}
|
|
Deletes a capability from the Amoeba directory tree.
|
|
Argument is the pathname.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{name_lookup}{path}
|
|
Looks up a capability.
|
|
Argument is the pathname.
|
|
Returns a
|
|
\dfn{capability}
|
|
object, to which various interesting operations apply, described below.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{name_replace}{path, cap}
|
|
Replaces a capability in the Amoeba directory tree.
|
|
Arguments are the pathname and the new capability.
|
|
(This differs from
|
|
\function{name_append()}
|
|
in the behavior when the pathname already exists:
|
|
\function{name_append()}
|
|
finds this an error while
|
|
\function{name_replace()}
|
|
allows it, as its name suggests.)
|
|
\end{funcdesc}
|
|
|
|
\begin{datadesc}{capv}
|
|
A table representing the capability environment at the time the
|
|
interpreter was started.
|
|
(Alas, modifying this table does not affect the capability environment
|
|
of the interpreter.)
|
|
For example,
|
|
\code{amoeba.capv['ROOT']}
|
|
is the capability of your root directory, similar to
|
|
\code{getcap("ROOT")}
|
|
in C.
|
|
\end{datadesc}
|
|
|
|
\begin{excdesc}{error}
|
|
The exception raised when an Amoeba function returns an error.
|
|
The value accompanying this exception is a pair containing the numeric
|
|
error code and the corresponding string, as returned by the C function
|
|
\cfunction{err_why()}.
|
|
\end{excdesc}
|
|
|
|
\begin{funcdesc}{timeout}{msecs}
|
|
Sets the transaction timeout, in milliseconds.
|
|
Returns the previous timeout.
|
|
Initially, the timeout is set to 2 seconds by the Python interpreter.
|
|
\end{funcdesc}
|
|
|
|
\subsection{Capability Operations}
|
|
|
|
Capabilities are written in a convenient \ASCII{} format, also used by the
|
|
Amoeba utilities
|
|
\emph{c2a}(U)
|
|
and
|
|
\emph{a2c}(U).
|
|
For example:
|
|
|
|
\begin{verbatim}
|
|
>>> amoeba.name_lookup('/profile/cap')
|
|
aa:1c:95:52:6a:fa/14(ff)/8e:ba:5b:8:11:1a
|
|
>>>
|
|
\end{verbatim}
|
|
%
|
|
The following methods are defined for capability objects.
|
|
|
|
\setindexsubitem{(capability method)}
|
|
\begin{funcdesc}{dir_list}{}
|
|
Returns a list of the names of the entries in an Amoeba directory.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{b_read}{offset, maxsize}
|
|
Reads (at most)
|
|
\var{maxsize}
|
|
bytes from a bullet file at offset
|
|
\var{offset.}
|
|
The data is returned as a string.
|
|
EOF is reported as an empty string.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{b_size}{}
|
|
Returns the size of a bullet file.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{dir_append}{}
|
|
\funcline{dir_delete}{}
|
|
\funcline{dir_lookup}{}
|
|
\funcline{dir_replace}{}
|
|
Like the corresponding
|
|
\samp{name_}*
|
|
functions, but with a path relative to the capability.
|
|
(For paths beginning with a slash the capability is ignored, since this
|
|
is the defined semantics for Amoeba.)
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{std_info}{}
|
|
Returns the standard info string of the object.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{tod_gettime}{}
|
|
Returns the time (in seconds since the Epoch, in UCT, as for \POSIX{}) from
|
|
a time server.
|
|
\end{funcdesc}
|
|
|
|
\begin{funcdesc}{tod_settime}{t}
|
|
Sets the time kept by a time server.
|
|
\end{funcdesc}
|