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Don't try to guess the name of a .def file -- if one is supplied, use it, otherwise just generate an '/export:' option.
author Greg Ward <gward@python.net>
date Thu, 29 Jun 2000 23:09:20 +0000
parents e82e82b3b9ad
children 563dee598d3a
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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1 \section{\module{Queue} ---
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2 A synchronized queue class.}
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3 \declaremodule{standard}{Queue}
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4
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5 \modulesynopsis{A synchronized queue class.}
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9 The \module{Queue} module implements a multi-producer, multi-consumer
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10 FIFO queue. It is especially useful in threads programming when
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11 information must be exchanged safely between multiple threads. The
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12 \class{Queue} class in this module implements all the required locking
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13 semantics. It depends on the availability of thread support in
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14 Python.
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15
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16 The \module{Queue} module defines the following class and exception:
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17
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19 \begin{classdesc}{Queue}{maxsize}
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20 Constructor for the class. \var{maxsize} is an integer that sets the
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21 upperbound limit on the number of items that can be placed in the
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22 queue. Insertion will block once this size has been reached, until
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23 queue items are consumed. If \var{maxsize} is less than or equal to
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24 zero, the queue size is infinite.
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25 \end{classdesc}
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26
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27 \begin{excdesc}{Empty}
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28 Exception raised when non-blocking \method{get()} (or
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29 \method{get_nowait()}) is called on a \class{Queue} object which is
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30 empty or locked.
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31 \end{excdesc}
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32
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33 \begin{excdesc}{Full}
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34 Exception raised when non-blocking \method{put()} (or
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35 \method{put_nowait()}) is called on a \class{Queue} object which is
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36 full or locked.
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37 \end{excdesc}
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39 \subsection{Queue Objects}
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40 \label{QueueObjects}
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41
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42 Class \class{Queue} implements queue objects and has the methods
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43 described below. This class can be derived from in order to implement
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44 other queue organizations (e.g. stack) but the inheritable interface
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45 is not described here. See the source code for details. The public
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46 methods are:
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47
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48 \begin{methoddesc}{qsize}{}
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49 Return the approximate size of the queue. Because of multithreading
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50 semantics, this number is not reliable.
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51 \end{methoddesc}
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53 \begin{methoddesc}{empty}{}
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54 Return \code{1} if the queue is empty, \code{0} otherwise. Because
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55 of multithreading semantics, this is not reliable.
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56 \end{methoddesc}
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58 \begin{methoddesc}{full}{}
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59 Return \code{1} if the queue is full, \code{0} otherwise. Because of
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60 multithreading semantics, this is not reliable.
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61 \end{methoddesc}
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63 \begin{methoddesc}{put}{item\optional{, block}}
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64 Put \var{item} into the queue. If optional argument \var{block} is 1
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65 (the default), block if necessary until a free slot is available.
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66 Otherwise (\var{block} is 0), put \var{item} on the queue if a free
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67 slot is immediately available, else raise the \exception{Full}
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68 exception.
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69 \end{methoddesc}
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71 \begin{methoddesc}{put_nowait}{item}
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72 Equivalent to \code{put(\var{item}, 0)}.
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73 \end{methoddesc}
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74
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75 \begin{methoddesc}{get}{\optional{block}}
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76 Remove and return an item from the queue. If optional argument
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77 \var{block} is 1 (the default), block if necessary until an item is
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78 available. Otherwise (\var{block} is 0), return an item if one is
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79 immediately available, else raise the
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80 \exception{Empty} exception.
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81 \end{methoddesc}
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82
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83 \begin{methoddesc}{get_nowait}{}
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84 Equivalent to \code{get(0)}.
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85 \end{methoddesc}