iochannels.sgml

GLib是GTK+和GNOME工程的基础底层核心程序库

</row>
<row>
<entry><literal>G_IO_CHANNEL_ERROR_NOSPC</literal></entry>
<entry>No space left on device.
</entry>
</row>
<row>
<entry><literal>G_IO_CHANNEL_ERROR_NXIO</literal></entry>
<entry>No such device or address.
</entry>
</row>
<row>
<entry><literal>G_IO_CHANNEL_ERROR_OVERFLOW</literal></entry>
<entry>Value too large for defined datatype.
</entry>
</row>
<row>
<entry><literal>G_IO_CHANNEL_ERROR_PIPE</literal></entry>
<entry>Broken pipe.
</entry>
</row>
<row>
<entry><literal>G_IO_CHANNEL_ERROR_FAILED</literal></entry>
<entry>Some other error.

</entry>
</row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="G-IO-CHANNEL-ERROR-CAPS">G_IO_CHANNEL_ERROR</title>
<programlisting>#define G_IO_CHANNEL_ERROR g_io_channel_error_quark()
</programlisting>
<para>
Error domain for <link linkend="GIOChannel">GIOChannel</link> operations. Errors in this domain will
be from the <link linkend="GIOChannelError">GIOChannelError</link> enumeration. See <link linkend="GError">GError</link> for information on
error domains.
</para></refsect2>
<refsect2>
<title><anchor id="g-io-channel-error-from-errno">g_io_channel_error_from_errno ()</title>
<programlisting><link linkend="GIOChannelError">GIOChannelError</link> g_io_channel_error_from_errno
                                            (<link linkend="gint">gint</link> en);</programlisting>
<para>
Converts an <literal>errno</literal> error number to a <link linkend="GIOChannelError">GIOChannelError</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>en</parameter>&nbsp;:</entry>
<entry> an <literal>errno</literal> error number, e.g. <literal>EINVAL</literal>.
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry> a <link linkend="GIOChannelError">GIOChannelError</link> error number, e.g. <literal>G_IO_CHANNEL_ERROR_INVAL</literal>.
</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-io-channel-ref">g_io_channel_ref ()</title>
<programlisting>void        g_io_channel_ref                (<link linkend="GIOChannel">GIOChannel</link> *channel);</programlisting>
<para>
Increments the reference count of a <link linkend="GIOChannel">GIOChannel</link>.
</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>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-io-channel-unref">g_io_channel_unref ()</title>
<programlisting>void        g_io_channel_unref              (<link linkend="GIOChannel">GIOChannel</link> *channel);</programlisting>
<para>
Decrements the reference count of a <link linkend="GIOChannel">GIOChannel</link>.
</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>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-io-create-watch">g_io_create_watch ()</title>
<programlisting><link linkend="GSource">GSource</link>*    g_io_create_watch               (<link linkend="GIOChannel">GIOChannel</link> *channel,
                                             <link linkend="GIOCondition">GIOCondition</link> condition);</programlisting>
<para>
Creates a <link linkend="GSource">GSource</link> that's dispatched when <parameter>condition</parameter> is met for the given
<parameter>channel</parameter>. For example, if condition is <link linkend="G-IO-IN-CAPS">G_IO_IN</link>, the source will be dispatched
when there's data available for reading.  <link linkend="g-io-add-watch">g_io_add_watch</link>() is a simpler
interface to this same functionality, for the case where you want to add the
source to the default main loop at the default priority.
</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> to watch
</entry></row>
<row><entry align="right"><parameter>condition</parameter>&nbsp;:</entry>
<entry>conditions to watch for
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry>a new <link linkend="GSource">GSource</link>


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-io-add-watch">g_io_add_watch ()</title>
<programlisting><link linkend="guint">guint</link>       g_io_add_watch                  (<link linkend="GIOChannel">GIOChannel</link> *channel,
                                             <link linkend="GIOCondition">GIOCondition</link> condition,
                                             <link linkend="GIOFunc">GIOFunc</link> func,
                                             <link linkend="gpointer">gpointer</link> user_data);</programlisting>
<para>
Adds the <link linkend="GIOChannel">GIOChannel</link> into the
<link linkend="glib-The-Main-Event-Loop">main event loop</link>
with the default priority.
</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>condition</parameter>&nbsp;:</entry>
<entry>the condition to watch for.
</entry></row>
<row><entry align="right"><parameter>func</parameter>&nbsp;:</entry>
<entry>the function to call when the condition is satisfied.
</entry></row>
<row><entry align="right"><parameter>user_data</parameter>&nbsp;:</entry>
<entry>user data to pass to <parameter>func</parameter>.
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry>the event source id.


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-io-add-watch-full">g_io_add_watch_full ()</title>
<programlisting><link linkend="guint">guint</link>       g_io_add_watch_full             (<link linkend="GIOChannel">GIOChannel</link> *channel,
                                             <link linkend="gint">gint</link> priority,
                                             <link linkend="GIOCondition">GIOCondition</link> condition,
                                             <link linkend="GIOFunc">GIOFunc</link> func,
                                             <link linkend="gpointer">gpointer</link> user_data,
                                             <link linkend="GDestroyNotify">GDestroyNotify</link> notify);</programlisting>
<para>
Adds the <link linkend="GIOChannel">GIOChannel</link> into the
<link linkend="glib-The-Main-Event-Loop">main event loop</link>
with the given priority.
</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>priority</parameter>&nbsp;:</entry>
<entry>the priority of the <link linkend="GIOChannel">GIOChannel</link> source.
</entry></row>
<row><entry align="right"><parameter>condition</parameter>&nbsp;:</entry>
<entry>the condition to watch for.
</entry></row>
<row><entry align="right"><parameter>func</parameter>&nbsp;:</entry>
<entry>the function to call when the condition is satisfied.
</entry></row>
<row><entry align="right"><parameter>user_data</parameter>&nbsp;:</entry>
<entry>user data to pass to <parameter>func</parameter>.
</entry></row>
<row><entry align="right"><parameter>notify</parameter>&nbsp;:</entry>
<entry>the function to call when the source is removed.
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry>the event source id.


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="GIOCondition">enum GIOCondition</title>
<programlisting>typedef enum
{
  G_IO_IN	GLIB_SYSDEF_POLLIN,
  G_IO_OUT	GLIB_SYSDEF_POLLOUT,
  G_IO_PRI	GLIB_SYSDEF_POLLPRI,
  G_IO_ERR	GLIB_SYSDEF_POLLERR,
  G_IO_HUP	GLIB_SYSDEF_POLLHUP,
  G_IO_NVAL	GLIB_SYSDEF_POLLNVAL
} GIOCondition;
</programlisting>
<para>
A bitwise combination representing a condition to watch for on an event
source.
</para><informaltable pgwide="1" frame="none" role="enum">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row>
<entry><literal>G_IO_IN</literal></entry>
<entry>There is data to read.
</entry>
</row>
<row>
<entry><literal>G_IO_OUT</literal></entry>
<entry>Data can be written (without blocking).
</entry>
</row>
<row>
<entry><literal>G_IO_PRI</literal></entry>
<entry>There is urgent data to read.
</entry>
</row>
<row>
<entry><literal>G_IO_ERR</literal></entry>
<entry>Error condition.
</entry>
</row>
<row>
<entry><literal>G_IO_HUP</literal></entry>
<entry>Hung up (the connection has been broken, usually for pipes 
           and sockets).
</entry>
</row>
<row>
<entry><literal>G_IO_NVAL</literal></entry>
<entry>Invalid request. The file descriptor is not open.

</entry>
</row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="GIOFunc">GIOFunc ()</title>
<programlisting><link linkend="gboolean">gboolean</link>    (*GIOFunc)                      (<link linkend="GIOChannel">GIOChannel</link> *source,
                                             <link linkend="GIOCondition">GIOCondition</link> condition,
                                             <link linkend="gpointer">gpointer</link> data);</programlisting>
<para>
Specifies the type of function passed to <link linkend="g-io-add-watch">g_io_add_watch</link>() or
<link linkend="g-io-add-watch-full">g_io_add_watch_full</link>(), which is called when the requested condition on a
<link linkend="GIOChannel">GIOChannel</link> is satisfied.
</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>source</parameter>&nbsp;:</entry>
<entry>the <link linkend="GIOChannel">GIOChannel</link> event source.
</entry></row>
<row><entry align="right"><parameter>condition</parameter>&nbsp;:</entry>
<entry>the condition which has been satisfied.
</entry></row>
<row><entry align="right"><parameter>data</parameter>&nbsp;:</entry>