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Previous: <a href="Linker-Functions.html#Linker-Functions" accesskey="p" rel="prev">Linker Functions</a>, Up: <a href="BFD-front-end.html#BFD-front-end" accesskey="u" rel="up">BFD front end</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="BFD-Index.html#BFD-Index" title="Index" rel="index">Index</a>]</p>
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<h3 class="section">2.18 Hash Tables</h3>
<a name="index-Hash-tables"></a>
<p>BFD provides a simple set of hash table functions.  Routines
are provided to initialize a hash table, to free a hash table,
to look up a string in a hash table and optionally create an
entry for it, and to traverse a hash table.  There is
currently no routine to delete an string from a hash table.
</p>
<p>The basic hash table does not permit any data to be stored
with a string.  However, a hash table is designed to present a
base class from which other types of hash tables may be
derived.  These derived types may store additional information
with the string.  Hash tables were implemented in this way,
rather than simply providing a data pointer in a hash table
entry, because they were designed for use by the linker back
ends.  The linker may create thousands of hash table entries,
and the overhead of allocating private data and storing and
following pointers becomes noticeable.
</p>
<p>The basic hash table code is in <code>hash.c</code>.
</p>
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<tr><td align="left" valign="top">&bull; <a href="Creating-and-Freeing-a-Hash-Table.html#Creating-and-Freeing-a-Hash-Table" accesskey="1">Creating and Freeing a Hash Table</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
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<tr><td align="left" valign="top">&bull; <a href="Looking-Up-or-Entering-a-String.html#Looking-Up-or-Entering-a-String" accesskey="2">Looking Up or Entering a String</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
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<tr><td align="left" valign="top">&bull; <a href="Traversing-a-Hash-Table.html#Traversing-a-Hash-Table" accesskey="3">Traversing a Hash Table</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
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<tr><td align="left" valign="top">&bull; <a href="Deriving-a-New-Hash-Table-Type.html#Deriving-a-New-Hash-Table-Type" accesskey="4">Deriving a New Hash Table Type</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
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