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diff --git a/doc/src/sgml/html/libpq-control.html b/doc/src/sgml/html/libpq-control.html new file mode 100644 index 0000000..25fcd0c --- /dev/null +++ b/doc/src/sgml/html/libpq-control.html @@ -0,0 +1,139 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>34.11. Control Functions</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="libpq-copy.html" title="34.10. Functions Associated with the COPY Command" /><link rel="next" href="libpq-misc.html" title="34.12. Miscellaneous Functions" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">34.11. Control Functions</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="libpq-copy.html" title="34.10. Functions Associated with the COPY Command">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="libpq.html" title="Chapter 34. libpq — C Library">Up</a></td><th width="60%" align="center">Chapter 34. <span class="application">libpq</span> — C Library</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.2 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="libpq-misc.html" title="34.12. Miscellaneous Functions">Next</a></td></tr></table><hr /></div><div class="sect1" id="LIBPQ-CONTROL"><div class="titlepage"><div><div><h2 class="title" style="clear: both">34.11. Control Functions <a href="#LIBPQ-CONTROL" class="id_link">#</a></h2></div></div></div><p> + These functions control miscellaneous details of <span class="application">libpq</span>'s + behavior. + </p><div class="variablelist"><dl class="variablelist"><dt id="LIBPQ-PQCLIENTENCODING"><span class="term"><code class="function">PQclientEncoding</code><a id="id-1.7.3.18.3.1.1.2" class="indexterm"></a></span> <a href="#LIBPQ-PQCLIENTENCODING" class="id_link">#</a></dt><dd><p> + Returns the client encoding. +</p><pre class="synopsis"> +int PQclientEncoding(const PGconn *<em class="replaceable"><code>conn</code></em>); +</pre><p> + + Note that it returns the encoding ID, not a symbolic string + such as <code class="literal">EUC_JP</code>. If unsuccessful, it returns -1. + To convert an encoding ID to an encoding name, you + can use: + +</p><pre class="synopsis"> +char *pg_encoding_to_char(int <em class="replaceable"><code>encoding_id</code></em>); +</pre><p> + </p></dd><dt id="LIBPQ-PQSETCLIENTENCODING"><span class="term"><code class="function">PQsetClientEncoding</code><a id="id-1.7.3.18.3.2.1.2" class="indexterm"></a></span> <a href="#LIBPQ-PQSETCLIENTENCODING" class="id_link">#</a></dt><dd><p> + Sets the client encoding. +</p><pre class="synopsis"> +int PQsetClientEncoding(PGconn *<em class="replaceable"><code>conn</code></em>, const char *<em class="replaceable"><code>encoding</code></em>); +</pre><p> + + <em class="replaceable"><code>conn</code></em> is a connection to the server, + and <em class="replaceable"><code>encoding</code></em> is the encoding you want to + use. If the function successfully sets the encoding, it returns 0, + otherwise -1. The current encoding for this connection can be + determined by using <a class="xref" href="libpq-control.html#LIBPQ-PQCLIENTENCODING"><code class="function">PQclientEncoding</code></a>. + </p></dd><dt id="LIBPQ-PQSETERRORVERBOSITY"><span class="term"><code class="function">PQsetErrorVerbosity</code><a id="id-1.7.3.18.3.3.1.2" class="indexterm"></a></span> <a href="#LIBPQ-PQSETERRORVERBOSITY" class="id_link">#</a></dt><dd><p> + Determines the verbosity of messages returned by + <a class="xref" href="libpq-status.html#LIBPQ-PQERRORMESSAGE"><code class="function">PQerrorMessage</code></a> and <a class="xref" href="libpq-exec.html#LIBPQ-PQRESULTERRORMESSAGE"><code class="function">PQresultErrorMessage</code></a>. +</p><pre class="synopsis"> +typedef enum +{ + PQERRORS_TERSE, + PQERRORS_DEFAULT, + PQERRORS_VERBOSE, + PQERRORS_SQLSTATE +} PGVerbosity; + +PGVerbosity PQsetErrorVerbosity(PGconn *conn, PGVerbosity verbosity); +</pre><p> + + <a class="xref" href="libpq-control.html#LIBPQ-PQSETERRORVERBOSITY"><code class="function">PQsetErrorVerbosity</code></a> sets the verbosity mode, + returning the connection's previous setting. + In <em class="firstterm">TERSE</em> mode, returned messages include + severity, primary text, and position only; this will normally fit on a + single line. The <em class="firstterm">DEFAULT</em> mode produces messages + that include the above plus any detail, hint, or context fields (these + might span multiple lines). The <em class="firstterm">VERBOSE</em> mode + includes all available fields. The <em class="firstterm">SQLSTATE</em> + mode includes only the error severity and the <code class="symbol">SQLSTATE</code> + error code, if one is available (if not, the output is like + <em class="firstterm">TERSE</em> mode). + </p><p> + Changing the verbosity setting does not affect the messages available + from already-existing <code class="structname">PGresult</code> objects, only + subsequently-created ones. + (But see <a class="xref" href="libpq-exec.html#LIBPQ-PQRESULTVERBOSEERRORMESSAGE"><code class="function">PQresultVerboseErrorMessage</code></a> if you + want to print a previous error with a different verbosity.) + </p></dd><dt id="LIBPQ-PQSETERRORCONTEXTVISIBILITY"><span class="term"><code class="function">PQsetErrorContextVisibility</code><a id="id-1.7.3.18.3.4.1.2" class="indexterm"></a></span> <a href="#LIBPQ-PQSETERRORCONTEXTVISIBILITY" class="id_link">#</a></dt><dd><p> + Determines the handling of <code class="literal">CONTEXT</code> fields in messages + returned by <a class="xref" href="libpq-status.html#LIBPQ-PQERRORMESSAGE"><code class="function">PQerrorMessage</code></a> + and <a class="xref" href="libpq-exec.html#LIBPQ-PQRESULTERRORMESSAGE"><code class="function">PQresultErrorMessage</code></a>. +</p><pre class="synopsis"> +typedef enum +{ + PQSHOW_CONTEXT_NEVER, + PQSHOW_CONTEXT_ERRORS, + PQSHOW_CONTEXT_ALWAYS +} PGContextVisibility; + +PGContextVisibility PQsetErrorContextVisibility(PGconn *conn, PGContextVisibility show_context); +</pre><p> + + <a class="xref" href="libpq-control.html#LIBPQ-PQSETERRORCONTEXTVISIBILITY"><code class="function">PQsetErrorContextVisibility</code></a> sets the context display mode, + returning the connection's previous setting. This mode controls + whether the <code class="literal">CONTEXT</code> field is included in messages. + The <em class="firstterm">NEVER</em> mode + never includes <code class="literal">CONTEXT</code>, while <em class="firstterm">ALWAYS</em> always + includes it if available. In <em class="firstterm">ERRORS</em> mode (the + default), <code class="literal">CONTEXT</code> fields are included only in error + messages, not in notices and warnings. + (However, if the verbosity setting is <em class="firstterm">TERSE</em> + or <em class="firstterm">SQLSTATE</em>, <code class="literal">CONTEXT</code> fields + are omitted regardless of the context display mode.) + </p><p> + Changing this mode does not + affect the messages available from + already-existing <code class="structname">PGresult</code> objects, only + subsequently-created ones. + (But see <a class="xref" href="libpq-exec.html#LIBPQ-PQRESULTVERBOSEERRORMESSAGE"><code class="function">PQresultVerboseErrorMessage</code></a> if you + want to print a previous error with a different display mode.) + </p></dd><dt id="LIBPQ-PQTRACE"><span class="term"><code class="function">PQtrace</code><a id="id-1.7.3.18.3.5.1.2" class="indexterm"></a></span> <a href="#LIBPQ-PQTRACE" class="id_link">#</a></dt><dd><p> + Enables tracing of the client/server communication to a debugging file + stream. +</p><pre class="synopsis"> +void PQtrace(PGconn *conn, FILE *stream); +</pre><p> + </p><p> + Each line consists of: an optional timestamp, a direction indicator + (<code class="literal">F</code> for messages from client to server + or <code class="literal">B</code> for messages from server to client), + message length, message type, and message contents. + Non-message contents fields (timestamp, direction, length and message type) + are separated by a tab. Message contents are separated by a space. + Protocol strings are enclosed in double quotes, while strings used as data + values are enclosed in single quotes. Non-printable chars are printed as + hexadecimal escapes. + Further message-type-specific detail can be found in + <a class="xref" href="protocol-message-formats.html" title="55.7. Message Formats">Section 55.7</a>. + </p><div class="note"><h3 class="title">Note</h3><p> + On Windows, if the <span class="application">libpq</span> library and an application are + compiled with different flags, this function call will crash the + application because the internal representation of the <code class="literal">FILE</code> + pointers differ. Specifically, multithreaded/single-threaded, + release/debug, and static/dynamic flags should be the same for the + library and all applications using that library. + </p></div></dd><dt id="LIBPQ-PQSETTRACEFLAGS"><span class="term"><code class="function">PQsetTraceFlags</code><a id="id-1.7.3.18.3.6.1.2" class="indexterm"></a></span> <a href="#LIBPQ-PQSETTRACEFLAGS" class="id_link">#</a></dt><dd><p> + Controls the tracing behavior of client/server communication. +</p><pre class="synopsis"> +void PQsetTraceFlags(PGconn *conn, int flags); +</pre><p> + </p><p> + <code class="literal">flags</code> contains flag bits describing the operating mode + of tracing. + If <code class="literal">flags</code> contains <code class="literal">PQTRACE_SUPPRESS_TIMESTAMPS</code>, + then the timestamp is not included when printing each message. + If <code class="literal">flags</code> contains <code class="literal">PQTRACE_REGRESS_MODE</code>, + then some fields are redacted when printing each message, such as object + OIDs, to make the output more convenient to use in testing frameworks. + This function must be called after calling <code class="function">PQtrace</code>. + </p></dd><dt id="LIBPQ-PQUNTRACE"><span class="term"><code class="function">PQuntrace</code><a id="id-1.7.3.18.3.7.1.2" class="indexterm"></a></span> <a href="#LIBPQ-PQUNTRACE" class="id_link">#</a></dt><dd><p> + Disables tracing started by <a class="xref" href="libpq-control.html#LIBPQ-PQTRACE"><code class="function">PQtrace</code></a>. +</p><pre class="synopsis"> +void PQuntrace(PGconn *conn); +</pre><p> + </p></dd></dl></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="libpq-copy.html" title="34.10. 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