kornerr
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research-portable-memory


			
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    <title>uthash: a hash table for C structures</title>
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  <a href="http://github.com/troydhanson/uthash">GitHub page</a> &gt;
  uthash home <!-- http://troydhanson.github.com/uthash/ -->

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        <h2>documentation</h2>
        <div><a href="userguide.html">uthash</a></div>
        <div><a href="utlist.html">utlist</a></div>
        <div><a href="utarray.html">utarray</a></div>
        <div><a href="utringbuffer.html">utringbuffer</a></div>
        <div><a href="utstack.html">utstack</a></div>
        <div><a href="utstring.html">utstring</a></div>

        <h2>download</h2>
        <h3>GNU/Linux, Windows</h3>
        <div><a href=https://github.com/troydhanson/uthash/archive/master.zip>uthash-master.zip</a></div>
        <div><a href=https://github.com/troydhanson/uthash>git clone</a></div>

        <h2>license</h2>
        <div><a href="license.html">BSD revised</a></div>


        <h2>developer</h2>
        <div><a href="http://troydhanson.github.io/">Troy D. Hanson</a></div>

        <h2>maintainer</h2>
        <div><a href="https://github.com/Quuxplusone">Arthur O'Dwyer</a></div>


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        Any C structure can be stored in a hash table using uthash. Just add a
        <em>UT_hash_handle</em> to the structure and choose one or more fields
        in your structure to act as the key. Then use these macros to store,
        retrieve or delete items from the hash table.

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Example 1. Adding an item to a hash.
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<pre>
#include "uthash.h"

struct my_struct {
    int id;            /* we'll use this field as the key */
    char name[10];
    UT_hash_handle hh; /* makes this structure hashable */
};

struct my_struct *users = NULL;

void add_user(struct my_struct *s) {
    HASH_ADD_INT(users, id, s);
}

</pre>
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Example 2. Looking up an item in a hash.
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<pre>
struct my_struct *find_user(int user_id) {
    struct my_struct *s;

    HASH_FIND_INT(users, &amp;user_id, s);
    return s;
}

</pre>
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Example 3. Deleting an item from a hash.
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<pre>
void delete_user(struct my_struct *user) {
    HASH_DEL(users, user);
}

</pre>
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 For more information and examples, please see the <a href="userguide.html">User Guide.</a>

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