38 lines
1.4 KiB
TeX
38 lines
1.4 KiB
TeX
\section{Built-in Module \sectcode{dbm}}
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\label{module-dbm}
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\bimodindex{dbm}
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The \code{dbm} module provides an interface to the \UNIX{}
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\code{(n)dbm} library. Dbm objects behave like mappings
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(dictionaries), except that keys and values are always strings.
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Printing a dbm object doesn't print the keys and values, and the
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\code{items()} and \code{values()} methods are not supported.
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See also the \code{gdbm} module, which provides a similar interface
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using the GNU GDBM library.
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\refbimodindex{gdbm}
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The module defines the following constant and functions:
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\setindexsubitem{(in module dbm)}
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\begin{excdesc}{error}
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Raised on dbm-specific errors, such as I/O errors. \code{KeyError} is
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raised for general mapping errors like specifying an incorrect key.
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\end{excdesc}
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\begin{funcdesc}{open}{filename\, \optional{flag\, \optional{mode}}}
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Open a dbm database and return a dbm object. The \var{filename}
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argument is the name of the database file (without the \file{.dir} or
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\file{.pag} extensions).
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The optional \var{flag} argument can be
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\code{'r'} (to open an existing database for reading only --- default),
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\code{'w'} (to open an existing database for reading and writing),
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\code{'c'} (which creates the database if it doesn't exist), or
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\code{'n'} (which always creates a new empty database).
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The optional \var{mode} argument is the \UNIX{} mode of the file, used
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only when the database has to be created. It defaults to octal
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\code{0666}.
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\end{funcdesc}
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