Doc/lib/libstatcache.tex

   1 \section{\module{statcache} ---
   2          An optimization of \function{os.stat()}}
   3
   4 \declaremodule{standard}{statcache}
   5 \sectionauthor{Moshe Zadka}{mzadka@geocities.com}
   6 \modulesynopsis{Stat files, and remember results.}
   7
   8 The \module{statcache} module provides a simple optimization to
   9 \function{os.stat()}: remembering the values of previous invocations.
  10
  11 The \module{statcache} module defines the following functions:
  12
  13 \begin{funcdesc}{stat}{path}
  14 This is the main module entry-point.
  15 Identical for \function{os.stat()}, except for remembering the result
  16 for future invocations of the function.
  17 \end{funcdesc}
  18
  19 The rest of the functions are used to clear the cache, or parts of
  20 it.
  21
  22 \begin{funcdesc}{reset}{}
  23 Clear the cache: forget all results of previous \function{stat()}
  24 calls.
  25 \end{funcdesc}
  26
  27 \begin{funcdesc}{forget}{path}
  28 Forget the result of \code{stat(\var{path})}, if any.
  29 \end{funcdesc}
  30
  31 \begin{funcdesc}{forget_prefix}{prefix}
  32 Forget all results of \code{stat(\var{path})} for \var{path} starting
  33 with \var{prefix}.
  34 \end{funcdesc}
  35
  36 \begin{funcdesc}{forget_dir}{prefix}
  37 Forget all results of \code{stat(\var{path})} for \var{path} a file in
  38 the directory \var{prefix}, including \code{stat(\var{prefix})}.
  39 \end{funcdesc}
  40
  41 \begin{funcdesc}{forget_except_prefix}{prefix}
  42 Similar to \function{forget_prefix()}, but for all \var{path} values
  43 \emph{not} starting with \var{prefix}.
  44 \end{funcdesc}
  45
  46 Example:
  47
  48 \begin{verbatim}
  49 >>> import os, statcache
  50 >>> statcache.stat('.')
  51 (16893, 2049, 772, 18, 1000, 1000, 2048, 929609777, 929609777, 929609777)
  52 >>> os.stat('.')
  53 (16893, 2049, 772, 18, 1000, 1000, 2048, 929609777, 929609777, 929609777)
  54 \end{verbatim}