iochannels.sgml

GLib是GTK+和GNOME工程的基础底层核心程序库

cases described in the documentation for <link linkend="g-io-channel-set-encoding">g_io_channel_set_encoding</link>().</para>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>channel</parameter>&nbsp;:</entry>
<entry> a <link linkend="GIOChannel">GIOChannel</link>
</entry></row>
<row><entry align="right"><parameter>buf</parameter>&nbsp;:</entry>
<entry> a buffer to write data from
</entry></row>
<row><entry align="right"><parameter>count</parameter>&nbsp;:</entry>
<entry> the size of the buffer. If -1, the buffer
        is taken to be a nul-terminated string.
</entry></row>
<row><entry align="right"><parameter>bytes_written</parameter>&nbsp;:</entry>
<entry> The number of bytes written. This can be nonzero
                even if the return value is not <literal>G_IO_STATUS_NORMAL</literal>.
                If the return value is <literal>G_IO_STATUS_NORMAL</literal> and the
                channel is blocking, this will always be equal
                to <parameter>count</parameter> if <parameter>count</parameter> >= 0.
</entry></row>
<row><entry align="right"><parameter>error</parameter>&nbsp;:</entry>
<entry> A location to return an error of type <link linkend="GConvertError">GConvertError</link>
        or <link linkend="GIOChannelError">GIOChannelError</link>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry> the status of the operation.
</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-io-channel-write-unichar">g_io_channel_write_unichar ()</title>
<programlisting><link linkend="GIOStatus">GIOStatus</link>   g_io_channel_write_unichar      (<link linkend="GIOChannel">GIOChannel</link> *channel,
                                             <link linkend="gunichar">gunichar</link> thechar,
                                             <link linkend="GError">GError</link> **error);</programlisting>
<para>
This function cannot be called on a channel with <literal>NULL</literal> encoding.</para>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>channel</parameter>&nbsp;:</entry>
<entry> a <link linkend="GIOChannel">GIOChannel</link>
</entry></row>
<row><entry align="right"><parameter>thechar</parameter>&nbsp;:</entry>
<entry> a character
</entry></row>
<row><entry align="right"><parameter>error</parameter>&nbsp;:</entry>
<entry> A location to return an error of type <link linkend="GConvertError">GConvertError</link>
        or <link linkend="GIOChannelError">GIOChannelError</link>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry> a <link linkend="GIOStatus">GIOStatus</link>
</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-io-channel-flush">g_io_channel_flush ()</title>
<programlisting><link linkend="GIOStatus">GIOStatus</link>   g_io_channel_flush              (<link linkend="GIOChannel">GIOChannel</link> *channel,
                                             <link linkend="GError">GError</link> **error);</programlisting>
<para>
Flushes the write buffer for the GIOChannel.</para>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>channel</parameter>&nbsp;:</entry>
<entry> a <link linkend="GIOChannel">GIOChannel</link>
</entry></row>
<row><entry align="right"><parameter>error</parameter>&nbsp;:</entry>
<entry> location to store an error of type <link linkend="GIOChannelError">GIOChannelError</link>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry> the status of the operation: One of
  <link linkend="G-IO-CHANNEL-NORMAL-CAPS">G_IO_CHANNEL_NORMAL</link>, <link linkend="G-IO-CHANNEL-AGAIN-CAPS">G_IO_CHANNEL_AGAIN</link>, or
  <link linkend="G-IO-CHANNEL-ERROR-CAPS">G_IO_CHANNEL_ERROR</link>.
</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-io-channel-seek-position">g_io_channel_seek_position ()</title>
<programlisting><link linkend="GIOStatus">GIOStatus</link>   g_io_channel_seek_position      (<link linkend="GIOChannel">GIOChannel</link> *channel,
                                             <link linkend="gint64">gint64</link> offset,
                                             <link linkend="GSeekType">GSeekType</link> type,
                                             <link linkend="GError">GError</link> **error);</programlisting>
<para>
Replacement for <link linkend="g-io-channel-seek">g_io_channel_seek</link>() with the new API.</para>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>channel</parameter>&nbsp;:</entry>
<entry> a <link linkend="GIOChannel">GIOChannel</link>
</entry></row>
<row><entry align="right"><parameter>offset</parameter>&nbsp;:</entry>
<entry> The offset in bytes from the position specified by <parameter>type</parameter>
</entry></row>
<row><entry align="right"><parameter>type</parameter>&nbsp;:</entry>
<entry> a <link linkend="GSeekType">GSeekType</link>. The type <literal>G_SEEK_CUR</literal> is only allowed in those
                     cases where a call to <link linkend="g-io-channel-set-encoding">g_io_channel_set_encoding</link>()
                     is allowed. See the documentation for
                     <link linkend="g-io-channel-set-encoding">g_io_channel_set_encoding</link>() for details.
</entry></row>
<row><entry align="right"><parameter>error</parameter>&nbsp;:</entry>
<entry> A location to return an error of type <link linkend="GIOChannelError">GIOChannelError</link>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry> the status of the operation.
</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="GSeekType">enum GSeekType</title>
<programlisting>typedef enum
{
  G_SEEK_CUR,
  G_SEEK_SET,
  G_SEEK_END
} GSeekType;
</programlisting>
<para>
An enumeration specifying the base position for a <link linkend="g-io-channel-seek-position">g_io_channel_seek_position</link>()
operation.
</para><informaltable pgwide="1" frame="none" role="enum">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row>
<entry><literal>G_SEEK_CUR</literal></entry>
<entry>the current position in the file.
</entry>
</row>
<row>
<entry><literal>G_SEEK_SET</literal></entry>
<entry>the start of the file.
</entry>
</row>
<row>
<entry><literal>G_SEEK_END</literal></entry>
<entry>the end of the file.

</entry>
</row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-io-channel-shutdown">g_io_channel_shutdown ()</title>
<programlisting><link linkend="GIOStatus">GIOStatus</link>   g_io_channel_shutdown           (<link linkend="GIOChannel">GIOChannel</link> *channel,
                                             <link linkend="gboolean">gboolean</link> flush,
                                             <link linkend="GError">GError</link> **err);</programlisting>
<para>
Close an IO channel. Any pending data to be written will be
flushed if <parameter>flush</parameter> is <literal>TRUE</literal>. The channel will not be freed until the
last reference is dropped using <link linkend="g-io-channel-unref">g_io_channel_unref</link>().</para>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>channel</parameter>&nbsp;:</entry>
<entry> a <link linkend="GIOChannel">GIOChannel</link>
</entry></row>
<row><entry align="right"><parameter>flush</parameter>&nbsp;:</entry>
<entry> if <literal>TRUE</literal>, flush pending
</entry></row>
<row><entry align="right"><parameter>err</parameter>&nbsp;:</entry>
<entry> location to store a <link linkend="GIOChannelError">GIOChannelError</link>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry> the status of the operation.
</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="GIOStatus">enum GIOStatus</title>
<programlisting>typedef enum
{
  G_IO_STATUS_ERROR,
  G_IO_STATUS_NORMAL,
  G_IO_STATUS_EOF,
  G_IO_STATUS_AGAIN
} GIOStatus;
</programlisting>
<para>
Stati returned by most of the <link linkend="GIOFuncs">GIOFuncs</link> functions. 
</para><informaltable pgwide="1" frame="none" role="enum">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row>
<entry><literal>G_IO_STATUS_ERROR</literal></entry>
<entry>An error occurred.
</entry>
</row>
<row>
<entry><literal>G_IO_STATUS_NORMAL</literal></entry>
<entry>Success.
</entry>
</row>
<row>
<entry><literal>G_IO_STATUS_EOF</literal></entry>
<entry>End of file.
</entry>
</row>
<row>
<entry><literal>G_IO_STATUS_AGAIN</literal></entry>
<entry>Resource temporarily unavailable.

</entry>
</row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="GIOChannelError">enum GIOChannelError</title>
<programlisting>typedef enum
{
  /* Derived from errno */
  G_IO_CHANNEL_ERROR_FBIG,
  G_IO_CHANNEL_ERROR_INVAL,
  G_IO_CHANNEL_ERROR_IO,
  G_IO_CHANNEL_ERROR_ISDIR,
  G_IO_CHANNEL_ERROR_NOSPC,
  G_IO_CHANNEL_ERROR_NXIO,
  G_IO_CHANNEL_ERROR_OVERFLOW,
  G_IO_CHANNEL_ERROR_PIPE,
  /* Other */
  G_IO_CHANNEL_ERROR_FAILED
} GIOChannelError;
</programlisting>
<para>
Error codes returned by <link linkend="GIOChannel">GIOChannel</link> operations.
</para><informaltable pgwide="1" frame="none" role="enum">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row>
<entry><literal>G_IO_CHANNEL_ERROR_FBIG</literal></entry>
<entry>File too large.
</entry>
</row>
<row>
<entry><literal>G_IO_CHANNEL_ERROR_INVAL</literal></entry>
<entry>Invalid argument.
</entry>
</row>
<row>
<entry><literal>G_IO_CHANNEL_ERROR_IO</literal></entry>
<entry>IO error.
</entry>
</row>
<row>
<entry><literal>G_IO_CHANNEL_ERROR_ISDIR</literal></entry>
<entry>File is a directory.
</entry>