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diff --git a/Doc/libgdbm.tex b/Doc/libgdbm.tex deleted file mode 100644 index 8f2d7d1..0000000 --- a/Doc/libgdbm.tex +++ /dev/null @@ -1,93 +0,0 @@ -\section{Built-in Module \module{gdbm}} -\label{module-gdbm} -\bimodindex{gdbm} - -% Note that if this section appears on the same page as the first -% paragraph of the dbm module section, makeindex will produce the -% warning: -% -% ## Warning (input = lib.idx, line = 1184; output = lib.ind, line = 852): -% -- Conflicting entries: multiple encaps for the same page under same key. -% -% This is because the \bimodindex{gdbm} and \refbimodindex{gdbm} -% entries in the .idx file are slightly different (the \bimodindex{} -% version includes "|textbf" at the end to make the defining occurance -% bold). There doesn't appear to be anything that can be done about -% this; it's just a little annoying. The warning can be ignored, but -% the index produced uses the non-bold version. - -This module is quite similar to the \code{dbm} module, but uses \code{gdbm} -instead to provide some additional functionality. Please note that -the file formats created by \code{gdbm} and \code{dbm} are incompatible. -\refbimodindex{dbm} - -The \code{gdbm} module provides an interface to the GNU DBM -library. \code{gdbm} objects behave like mappings -(dictionaries), except that keys and values are always strings. -Printing a \code{gdbm} object doesn't print the keys and values, and the -\code{items()} and \code{values()} methods are not supported. - -The module defines the following constant and functions: - -\begin{excdesc}{error} -Raised on \code{gdbm}-specific errors, such as I/O errors. \code{KeyError} is -raised for general mapping errors like specifying an incorrect key. -\end{excdesc} - -\begin{funcdesc}{open}{filename, \optional{flag, \optional{mode}}} -Open a \code{gdbm} database and return a \code{gdbm} object. The -\var{filename} argument is the name of the database file. - -The optional \var{flag} argument can be -\code{'r'} (to open an existing database for reading only --- default), -\code{'w'} (to open an existing database for reading and writing), -\code{'c'} (which creates the database if it doesn't exist), or -\code{'n'} (which always creates a new empty database). - -Appending \code{f} to the flag opens the database in fast mode; -altered data will not automatically be written to the disk after every -change. This results in faster writes to the database, but may result -in an inconsistent database if the program crashes while the database -is still open. Use the \code{sync()} method to force any unwritten -data to be written to the disk. - -The optional \var{mode} argument is the \UNIX{} mode of the file, used -only when the database has to be created. It defaults to octal -\code{0666}. -\end{funcdesc} - -In addition to the dictionary-like methods, \code{gdbm} objects have the -following methods: - -\begin{funcdesc}{firstkey}{} -It's possible to loop over every key in the database using this method -and the \code{nextkey()} method. The traversal is ordered by \code{gdbm}'s -internal hash values, and won't be sorted by the key values. This -method returns the starting key. -\end{funcdesc} - -\begin{funcdesc}{nextkey}{key} -Returns the key that follows \var{key} in the traversal. The -following code prints every key in the database \code{db}, without having to -create a list in memory that contains them all: -\begin{verbatim} -k=db.firstkey() -while k!=None: - print k - k=db.nextkey(k) -\end{verbatim} -\end{funcdesc} - -\begin{funcdesc}{reorganize}{} -If you have carried out a lot of deletions and would like to shrink -the space used by the \code{gdbm} file, this routine will reorganize the -database. \code{gdbm} will not shorten the length of a database file except -by using this reorganization; otherwise, deleted file space will be -kept and reused as new (key,value) pairs are added. -\end{funcdesc} - -\begin{funcdesc}{sync}{} -When the database has been opened in fast mode, this method forces any -unwritten data to be written to the disk. -\end{funcdesc} - |