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43th chunk of `doc/src/sgml/spi.sgml`
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 <refmeta>
  <refentrytitle>SPI_repalloc</refentrytitle>
  <manvolnum>3</manvolnum>
 </refmeta>

 <refnamediv>
  <refname>SPI_repalloc</refname>
  <refpurpose>reallocate memory in the upper executor context</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
<synopsis>
void * SPI_repalloc(void * <parameter>pointer</parameter>, Size <parameter>size</parameter>)
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <function>SPI_repalloc</function> changes the size of a memory
   segment previously allocated using <function>SPI_palloc</function>.
  </para>

  <para>
   This function is no longer different from plain
   <function>repalloc</function>.  It's kept just for backward
   compatibility of existing code.
  </para>
 </refsect1>

 <refsect1>
  <title>Arguments</title>

  <variablelist>
   <varlistentry>
    <term><literal>void * <parameter>pointer</parameter></literal></term>
    <listitem>
     <para>
      pointer to existing storage to change
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>Size <parameter>size</parameter></literal></term>
    <listitem>
     <para>
      size in bytes of storage to allocate
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect1>

 <refsect1>
  <title>Return Value</title>

  <para>
   pointer to new storage space of specified size with the contents
   copied from the existing area
  </para>
 </refsect1>
</refentry>

<!-- *********************************************** -->

<refentry id="spi-spi-pfree">
 <indexterm><primary>SPI_pfree</primary></indexterm>

 <refmeta>
  <refentrytitle>SPI_pfree</refentrytitle>
  <manvolnum>3</manvolnum>
 </refmeta>

 <refnamediv>
  <refname>SPI_pfree</refname>
  <refpurpose>free memory in the upper executor context</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
<synopsis>
void SPI_pfree(void * <parameter>pointer</parameter>)
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <function>SPI_pfree</function> frees memory previously allocated
   using <function>SPI_palloc</function> or
   <function>SPI_repalloc</function>.
  </para>

  <para>
   This function is no longer different from plain
   <function>pfree</function>.  It's kept just for backward
   compatibility of existing code.
  </para>
 </refsect1>

 <refsect1>
  <title>Arguments</title>

  <variablelist>
   <varlistentry>
    <term><literal>void * <parameter>pointer</parameter></literal></term>
    <listitem>
     <para>
      pointer to existing storage to free
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect1>
</refentry>

<!-- *********************************************** -->

<refentry id="spi-spi-copytuple">
 <indexterm><primary>SPI_copytuple</primary></indexterm>

 <refmeta>
  <refentrytitle>SPI_copytuple</refentrytitle>
  <manvolnum>3</manvolnum>
 </refmeta>

 <refnamediv>
  <refname>SPI_copytuple</refname>
  <refpurpose>make a copy of a row in the upper executor context</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
<synopsis>
HeapTuple SPI_copytuple(HeapTuple <parameter>row</parameter>)
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <function>SPI_copytuple</function> makes a copy of a row in the
   upper executor context.  This is normally used to return a modified
   row from a trigger.  In a function declared to return a composite
   type, use <function>SPI_returntuple</function> instead.
  </para>

  <para>
   This function can only be used while connected to SPI.
   Otherwise, it returns NULL and sets <varname>SPI_result</varname> to
   <symbol>SPI_ERROR_UNCONNECTED</symbol>.
  </para>
 </refsect1>

 <refsect1>
  <title>Arguments</title>

  <variablelist>
   <varlistentry>
    <term><literal>HeapTuple <parameter>row</parameter></literal></term>
    <listitem>
     <para>
      row to be copied
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect1>

 <refsect1>
  <title>Return
Title: SPI Memory Management Functions: SPI_repalloc, SPI_pfree, and SPI_copytuple
Summary
This section details three SPI functions related to memory management and tuple manipulation. `SPI_repalloc` reallocates memory previously allocated by `SPI_palloc`, although it's now functionally identical to `repalloc` and maintained for backward compatibility. `SPI_pfree` frees memory allocated by `SPI_palloc` or `SPI_repalloc`, and is now equivalent to `pfree`. Finally, `SPI_copytuple` creates a copy of a row (HeapTuple) in the upper executor context, typically used for returning modified rows from a trigger. It returns NULL if not connected to SPI.