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diff --git a/static/freebsd/man4/ng_tty.4 3.html b/static/freebsd/man4/ng_tty.4 3.html new file mode 100644 index 00000000..4e8294cc --- /dev/null +++ b/static/freebsd/man4/ng_tty.4 3.html @@ -0,0 +1,114 @@ +<table class="head"> + <tr> + <td class="head-ltitle">NG_TTY(4)</td> + <td class="head-vol">Device Drivers Manual</td> + <td class="head-rtitle">NG_TTY(4)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">ng_tty</code> — <span class="Nd">netgraph + node type that is also a TTY hook</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp"><code class="In">#include + <<a class="In">sys/types.h</a>></code> + <br/> + <code class="In">#include <<a class="In">sys/ttycom.h</a>></code> + <br/> + <code class="In">#include + <<a class="In">netgraph/ng_tty.h</a>></code></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The <code class="Nm">tty</code> node type is both a netgraph node + type and a TTY hook.</p> +<p class="Pp">The node has a single hook called <code class="Dv">hook</code>. + Incoming bytes received on the tty device are sent out on this hook, and + frames received on <code class="Dv">hook</code> are transmitted out on the + tty device. No modification to the data is performed in either direction. + While the hook is installed on a tty, the normal read and write operations + are unavailable, returning <code class="Er">EIO</code>.</p> +<p class="Pp">Incoming data is delivered directly to ng_tty via the tty bypass + hook as a buffer pointer and length, this is converted to a mbuf and passed + to the peer.</p> +<p class="Pp">The node supports an optional “hot character”. If + the driver can not deliver data directly to the tty bypass hook then each + character is input one at a time. If set to non-zero and bypass mode is + unavailable, incoming data from the tty device is queued until this + character is seen. This avoids sending lots of mbufs containing a small + number of bytes, but introduces potentially infinite latency. The default + hot character is 0x7e, consistent with <code class="Dv">hook</code> being + connected to a <a class="Xr">ng_async(4)</a> type node. The hot character + has no effect on the transmission of data.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HOOKS"><a class="permalink" href="#HOOKS">HOOKS</a></h1> +<p class="Pp">This node type supports the following hooks:</p> +<dl class="Bl-tag"> + <dt id="hook"><var class="Va">hook</var></dt> + <dd><a class="Xr">tty(4)</a> serial data contained in + <code class="Dv">mbuf</code> structures, with arbitrary inter-frame + boundaries.</dd> +</dl> +</section> +<section class="Sh"> +<h1 class="Sh" id="CONTROL_MESSAGES"><a class="permalink" href="#CONTROL_MESSAGES">CONTROL + MESSAGES</a></h1> +<p class="Pp">This node type supports the generic control messages, plus the + following:</p> +<dl class="Bl-tag"> + <dt id="NGM_TTY_SET_HOTCHAR"><a class="permalink" href="#NGM_TTY_SET_HOTCHAR"><code class="Dv">NGM_TTY_SET_HOTCHAR</code></a></dt> + <dd>This command takes an integer argument and sets the hot character from the + lower 8 bits. A hot character of zero disables queueing, so that all + received data is forwarded immediately.</dd> + <dt id="NGM_TTY_GET_HOTCHAR"><a class="permalink" href="#NGM_TTY_GET_HOTCHAR"><code class="Dv">NGM_TTY_GET_HOTCHAR</code></a></dt> + <dd>Returns an integer containing the current hot character in the lower eight + bits.</dd> + <dt id="NGM_TTY_SET_TTY"><a class="permalink" href="#NGM_TTY_SET_TTY"><code class="Dv">NGM_TTY_SET_TTY</code></a></dt> + <dd>This command takes integer process ID and file descriptor of open tty and + registers the tty hooks.</dd> +</dl> +</section> +<section class="Sh"> +<h1 class="Sh" id="SHUTDOWN"><a class="permalink" href="#SHUTDOWN">SHUTDOWN</a></h1> +<p class="Pp">This node shuts down when the corresponding device is closed.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">ioctl(2)</a>, <a class="Xr">netgraph(4)</a>, + <a class="Xr">ng_async(4)</a>, <a class="Xr">tty(4)</a>, + <a class="Xr">ngctl(8)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Nm">ng_tty</code> node type was implemented in + <span class="Ux">FreeBSD 4.0</span>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1> +<p class="Pp"><span class="An">Archie Cobbs</span> + <<a class="Mt" href="mailto:archie@FreeBSD.org">archie@FreeBSD.org</a>> + <br/> + <span class="An">Andrew Thompson</span> + <<a class="Mt" href="mailto:thompsa@FreeBSD.org">thompsa@FreeBSD.org</a>></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="BUGS"><a class="permalink" href="#BUGS">BUGS</a></h1> +<p class="Pp">The serial driver code also has a notion of a “hot + character”. Unfortunately, this value is statically defined in terms + of the line discipline and cannot be changed. Therefore, if a hot character + other than 0x7e (the default) is set for the <code class="Nm">ng_tty</code> + node, the node has no way to convey this information to the serial driver, + and sub-optimal performance may result.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">December 25, 2008</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |