order, but
    conventionally <function>errcode</function>
    and <function>errmsg</function> appear first.
   </para>

   <para>
    If the severity level is <literal>ERROR</literal> or higher,
    <function>ereport</function> aborts execution of the current query
    and does not return to the caller. If the severity level is
    lower than <literal>ERROR</literal>, <function>ereport</function> returns normally.
   </para>

   <para>
    The available auxiliary routines for <function>ereport</function> are:
  <itemizedlist>
   <listitem>
    <para>
     <function>errcode(sqlerrcode)</function> specifies the SQLSTATE error identifier
     code for the condition.  If this routine is not called, the error
     identifier defaults to
     <literal>ERRCODE_INTERNAL_ERROR</literal> when the error severity level is
     <literal>ERROR</literal> or higher, <literal>ERRCODE_WARNING</literal> when the
     error level is <literal>WARNING</literal>, otherwise (for <literal>NOTICE</literal>
     and below) <literal>ERRCODE_SUCCESSFUL_COMPLETION</literal>.
     While these defaults are often convenient, always think whether they
     are appropriate before omitting the <function>errcode()</function> call.
    </para>
   </listitem>
   <listitem>
    <para>
     <function>errmsg(const char *msg, ...)</function> specifies the primary error
     message text, and possibly run-time values to insert into it.  Insertions
     are specified by <function>sprintf</function>-style format codes.  In addition to
     the standard format codes accepted by <function>sprintf</function>, the format
     code <literal>%m</literal> can be used to insert the error message returned
     by <function>strerror</function> for the current value of <literal>errno</literal>.
     <footnote>
      <para>
       That is, the value that was current when the <function>ereport</function> call
       was reached; changes of <literal>errno</literal> within the auxiliary reporting
       routines will not affect it.  That would not be true if you were to
       write <literal>strerror(errno)</literal> explicitly in <function>errmsg</function>'s
       parameter list; accordingly, do not do so.
      </para>
     </footnote>
     <literal>%m</literal> does not require any
     corresponding entry in the parameter list for <function>errmsg</function>.
     Note that the message string will be run through <function>gettext</function>
     for possible localization before format codes are processed.
    </para>
   </listitem>
   <listitem>
    <para>
     <function>errmsg_internal(const char *msg, ...)</function> is the same as
     <function>errmsg</function>, except that the message string will not be
     translated nor included in the internationalization message dictionary.
     This should be used for <quote>cannot happen</quote> cases that are probably
     not worth expending translation effort on.
    </para>
   </listitem>
   <listitem>
    <para>
     <function>errmsg_plural(const char *fmt_singular, const char *fmt_plural,
     unsigned long n, ...)</function> is like <function>errmsg</function>, but with
     support for various plural forms of the message.
     <replaceable>fmt_singular</replaceable> is the English singular format,
     <replaceable>fmt_plural</replaceable> is the English plural format,
     <replaceable>n</replaceable> is the integer value that determines which plural
     form is needed, and the remaining arguments are formatted according
     to the selected format string.  For more information see
     <xref linkend="nls-guidelines"/>.
    </para>
   </listitem>
   <listitem>
    <para>
     <function>errdetail(const char *msg, ...)</function> supplies an optional
     <quote>detail</quote> message; this is to be used when there is additional
     information that seems inappropriate to put in the primary message.
     The message string is processed in just the same way as for
     <function>errmsg</function>.
    </para>
   </listitem>