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36 lines
1.1 KiB
TeX
36 lines
1.1 KiB
TeX
\section{\module{cmpcache} ---
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Efficient file comparisons}
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\declaremodule{standard}{cmpcache}
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\sectionauthor{Moshe Zadka}{mzadka@geocities.com}
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\modulesynopsis{Compare files very efficiently.}
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The \module{cmpcache} module defines a function to compare files, taking all
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sort of short-cuts to make it a highly efficient operation.
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The \module{cmpcache} module defines the following function:
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\begin{funcdesc}{cmp}{f1, f2}
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Compare two files given as names. The following tricks are used to
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optimize the comparisons:
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\begin{itemize}
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\item Signatures (type, size and mtime) are computed via
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\refmodule{statcache}
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\item Files with identical type, size and mtime are assumed equal.
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\item Files with different type or size are never equal.
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\item The module only compares files it already compared if their
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signature changed.
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\item No external programs are called.
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\end{itemize}
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\end{funcdesc}
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Example:
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\begin{verbatim}
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>>> import cmpcache
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>>> cmpcache.cmp('libundoc.tex', 'libundoc.tex')
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1
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>>> cmpcache.cmp('libundoc.tex', 'lib.tex')
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0
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\end{verbatim}
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