1*91df013fSAsim Jamshed<!-- Creator     : groff version 1.22.2 -->
2*91df013fSAsim Jamshed<!-- CreationDate: Fri Feb  3 15:37:41 2017 -->
3*91df013fSAsim Jamshed<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
4*91df013fSAsim Jamshed"http://www.w3.org/TR/html4/loose.dtd">
5*91df013fSAsim Jamshed<html>
6*91df013fSAsim Jamshed<head>
7*91df013fSAsim Jamshed<meta name="generator" content="groff -Thtml, see www.gnu.org">
8*91df013fSAsim Jamshed<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
9*91df013fSAsim Jamshed<meta name="Content-Style" content="text/css">
10*91df013fSAsim Jamshed<style type="text/css">
11*91df013fSAsim Jamshed       p       { margin-top: 0; margin-bottom: 0; vertical-align: top }
12*91df013fSAsim Jamshed       pre     { margin-top: 0; margin-bottom: 0; vertical-align: top }
13*91df013fSAsim Jamshed       table   { margin-top: 0; margin-bottom: 0; vertical-align: top }
14*91df013fSAsim Jamshed       h1      { text-align: center }
15*91df013fSAsim Jamshed</style>
16*91df013fSAsim Jamshed<title>mtcp_ppeek</title>
17*91df013fSAsim Jamshed
18*91df013fSAsim Jamshed</head>
19*91df013fSAsim Jamshed<body>
20*91df013fSAsim Jamshed
21*91df013fSAsim Jamshed<h1 align="center">mtcp_ppeek</h1>
22*91df013fSAsim Jamshed
23*91df013fSAsim Jamshed<a href="#NAME">NAME</a><br>
24*91df013fSAsim Jamshed<a href="#SYNOPSIS">SYNOPSIS</a><br>
25*91df013fSAsim Jamshed<a href="#DESCRIPTION">DESCRIPTION</a><br>
26*91df013fSAsim Jamshed<a href="#RETURN VALUE">RETURN VALUE</a><br>
27*91df013fSAsim Jamshed<a href="#ERRORS">ERRORS</a><br>
28*91df013fSAsim Jamshed<a href="#AUTHORS">AUTHORS</a><br>
29*91df013fSAsim Jamshed<a href="#SEE ALSO">SEE ALSO</a><br>
30*91df013fSAsim Jamshed<a href="#COLOPHON">COLOPHON</a><br>
31*91df013fSAsim Jamshed
32*91df013fSAsim Jamshed<hr>
33*91df013fSAsim Jamshed
34*91df013fSAsim Jamshed
35*91df013fSAsim Jamshed<h2>NAME
36*91df013fSAsim Jamshed<a name="NAME"></a>
37*91df013fSAsim Jamshed</h2>
38*91df013fSAsim Jamshed
39*91df013fSAsim Jamshed
40*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">mtcp_ppeek
41*91df013fSAsim Jamshed&minus; Peek into the bytestream from a monitoring socket
42*91df013fSAsim Jamshedfrom a given offset</p>
43*91df013fSAsim Jamshed
44*91df013fSAsim Jamshed<h2>SYNOPSIS
45*91df013fSAsim Jamshed<a name="SYNOPSIS"></a>
46*91df013fSAsim Jamshed</h2>
47*91df013fSAsim Jamshed
48*91df013fSAsim Jamshed
49*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em"><b>#include
50*91df013fSAsim Jamshed&lt;mos_api.h&gt;</b></p>
51*91df013fSAsim Jamshed
52*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em"><b>ssize_t
53*91df013fSAsim Jamshedmtcp_ppeek(mctx_t</b> <i>mctx</i><b>, int</b>
54*91df013fSAsim Jamshed<i>sockid</i><b>, int</b> <i>side</i><b>, char
55*91df013fSAsim Jamshed*</b><i>buf</i><b>, size_t</b> <i>len</i><b>, uint64_t</b>
56*91df013fSAsim Jamshed<i>off</i><b>);</b></p>
57*91df013fSAsim Jamshed
58*91df013fSAsim Jamshed<h2>DESCRIPTION
59*91df013fSAsim Jamshed<a name="DESCRIPTION"></a>
60*91df013fSAsim Jamshed</h2>
61*91df013fSAsim Jamshed
62*91df013fSAsim Jamshed
63*91df013fSAsim Jamshed
64*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em"><b>mtcp_ppeek</b>()
65*91df013fSAsim Jamshedcan be used to peek up to <i>len</i> number of bytes from a
66*91df013fSAsim Jamshedmonitoring socket via socket descriptor <i>sockid</i> into
67*91df013fSAsim Jamshedthe buffer starting at <i>buf. from off ;</i> value which is
68*91df013fSAsim Jamshedthe offset distance (in bytes) from the TCP initial sequence
69*91df013fSAsim Jamshednumber. It is the responsibility of the user to allocate
70*91df013fSAsim Jamshedmemory for <i>buf</i> array.</p>
71*91df013fSAsim Jamshed
72*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">For cases when
73*91df013fSAsim Jamshedthe total number of buffered unread bytes in the socket are
74*91df013fSAsim Jamshedless than <i>len,</i> <b>mtcp_ppeek()</b> copies entire data
75*91df013fSAsim Jamshedto <i>buf</i> and returns the actual number of bytes that
76*91df013fSAsim Jamshedcan be used by the application.</p>
77*91df013fSAsim Jamshed
78*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">Note that the
79*91df013fSAsim Jamshed<i>off</i> can also point to the data in the fragmented
80*91df013fSAsim Jamshedbuffer list of the TCP ring buffer (see
81*91df013fSAsim Jamshed<b>mtcp_getsockopt()).</b> If there is no received byte at
82*91df013fSAsim Jamshed<i>off</i> in the TCP ring buffer, it returns error. If
83*91df013fSAsim Jamshedthere are received bytes starting from <i>off ,</i> len is
84*91df013fSAsim Jamshedset to be the number of bytes read from the buffer. After
85*91df013fSAsim Jamshed<b>mtcp_ppeek(),</b> the data in the TCP ring buffer will
86*91df013fSAsim Jamshednot be flushed, and the monitor offset used by
87*91df013fSAsim Jamshed<b>mtcp_peek()</b> is not changed.</p>
88*91df013fSAsim Jamshed
89*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">An
90*91df013fSAsim Jamshed<b>mtcp_ppeek</b>() call takes two additional argument named
91*91df013fSAsim Jamshed<i>mctx ,</i> that represents the per-core mTCP context in
92*91df013fSAsim Jamshedan application (see <b>mtcp_create_context()</b> for
93*91df013fSAsim Jamsheddetails); and <i>side</i> that informs the stack whether it
94*91df013fSAsim Jamshedneeds to peek the client (MOS_SIDE_CLI) or server
95*91df013fSAsim Jamshed(MOS_SIDE_SVR) side.</p>
96*91df013fSAsim Jamshed
97*91df013fSAsim Jamshed<h2>RETURN VALUE
98*91df013fSAsim Jamshed<a name="RETURN VALUE"></a>
99*91df013fSAsim Jamshed</h2>
100*91df013fSAsim Jamshed
101*91df013fSAsim Jamshed
102*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">On success, the
103*91df013fSAsim Jamshednumber of bytes read is returned. It is not an error if this
104*91df013fSAsim Jamshednumber is smaller than the number of bytes requested; this
105*91df013fSAsim Jamshedmay happen when the socket has fewer number of bytes
106*91df013fSAsim Jamshedbuffered at that moment. On all errors, -1 is returned and
107*91df013fSAsim Jamshed<i>errno</i> is set appropriately.</p>
108*91df013fSAsim Jamshed
109*91df013fSAsim Jamshed<h2>ERRORS
110*91df013fSAsim Jamshed<a name="ERRORS"></a>
111*91df013fSAsim Jamshed</h2>
112*91df013fSAsim Jamshed
113*91df013fSAsim Jamshed
114*91df013fSAsim Jamshed<table width="100%" border="0" rules="none" frame="void"
115*91df013fSAsim Jamshed       cellspacing="0" cellpadding="0">
116*91df013fSAsim Jamshed<tr valign="top" align="left">
117*91df013fSAsim Jamshed<td width="11%"></td>
118*91df013fSAsim Jamshed<td width="23%">
119*91df013fSAsim Jamshed
120*91df013fSAsim Jamshed
121*91df013fSAsim Jamshed<p style="margin-top: 1em"><b>EACCES</b></p></td>
122*91df013fSAsim Jamshed<td width="4%"></td>
123*91df013fSAsim Jamshed<td width="62%">
124*91df013fSAsim Jamshed
125*91df013fSAsim Jamshed
126*91df013fSAsim Jamshed<p style="margin-top: 1em">The <i>mctx</i> argument is
127*91df013fSAsim Jamshedinvalid.</p> </td></tr>
128*91df013fSAsim Jamshed<tr valign="top" align="left">
129*91df013fSAsim Jamshed<td width="11%"></td>
130*91df013fSAsim Jamshed<td width="23%">
131*91df013fSAsim Jamshed
132*91df013fSAsim Jamshed
133*91df013fSAsim Jamshed<p><b>EBADF</b></p></td>
134*91df013fSAsim Jamshed<td width="4%"></td>
135*91df013fSAsim Jamshed<td width="62%">
136*91df013fSAsim Jamshed
137*91df013fSAsim Jamshed
138*91df013fSAsim Jamshed<p>The socket descriptor <i>sockid</i> is invalid.</p></td></tr>
139*91df013fSAsim Jamshed<tr valign="top" align="left">
140*91df013fSAsim Jamshed<td width="11%"></td>
141*91df013fSAsim Jamshed<td width="23%">
142*91df013fSAsim Jamshed
143*91df013fSAsim Jamshed
144*91df013fSAsim Jamshed<p><b>EINVAL</b></p></td>
145*91df013fSAsim Jamshed<td width="4%"></td>
146*91df013fSAsim Jamshed<td width="62%">
147*91df013fSAsim Jamshed
148*91df013fSAsim Jamshed
149*91df013fSAsim Jamshed<p>The buffer management of the monitoring socket with
150*91df013fSAsim Jamshed<i>sockid</i> was already disabled.</p></td></tr>
151*91df013fSAsim Jamshed<tr valign="top" align="left">
152*91df013fSAsim Jamshed<td width="11%"></td>
153*91df013fSAsim Jamshed<td width="23%">
154*91df013fSAsim Jamshed
155*91df013fSAsim Jamshed
156*91df013fSAsim Jamshed<p><b>ESOCKTNOSUPPORT</b></p></td>
157*91df013fSAsim Jamshed<td width="4%"></td>
158*91df013fSAsim Jamshed<td width="62%">
159*91df013fSAsim Jamshed
160*91df013fSAsim Jamshed
161*91df013fSAsim Jamshed<p>The socket referred to by <i>sockid</i> has invalid
162*91df013fSAsim Jamshed<i>type</i></p> </td></tr>
163*91df013fSAsim Jamshed<tr valign="top" align="left">
164*91df013fSAsim Jamshed<td width="11%"></td>
165*91df013fSAsim Jamshed<td width="23%">
166*91df013fSAsim Jamshed
167*91df013fSAsim Jamshed
168*91df013fSAsim Jamshed<p><b>ENOTCONN</b></p></td>
169*91df013fSAsim Jamshed<td width="4%"></td>
170*91df013fSAsim Jamshed<td width="62%">
171*91df013fSAsim Jamshed
172*91df013fSAsim Jamshed
173*91df013fSAsim Jamshed<p>Th socket referred to by <i>sockid</i> is in a TCP state
174*91df013fSAsim Jamshedthat disallows read operations.</p></td></tr>
175*91df013fSAsim Jamshed<tr valign="top" align="left">
176*91df013fSAsim Jamshed<td width="11%"></td>
177*91df013fSAsim Jamshed<td width="23%">
178*91df013fSAsim Jamshed
179*91df013fSAsim Jamshed
180*91df013fSAsim Jamshed<p><b>ENODATA</b></p></td>
181*91df013fSAsim Jamshed<td width="4%"></td>
182*91df013fSAsim Jamshed<td width="62%">
183*91df013fSAsim Jamshed
184*91df013fSAsim Jamshed
185*91df013fSAsim Jamshed<p>The socket referred to by <i>sockid</i> does not have
186*91df013fSAsim Jamshedany available bytes in its buffer for reading.</p></td></tr>
187*91df013fSAsim Jamshed<tr valign="top" align="left">
188*91df013fSAsim Jamshed<td width="11%"></td>
189*91df013fSAsim Jamshed<td width="23%">
190*91df013fSAsim Jamshed
191*91df013fSAsim Jamshed
192*91df013fSAsim Jamshed<p><b>EPERM</b></p></td>
193*91df013fSAsim Jamshed<td width="4%"></td>
194*91df013fSAsim Jamshed<td width="62%">
195*91df013fSAsim Jamshed
196*91df013fSAsim Jamshed
197*91df013fSAsim Jamshed<p>The caller is not permitted to access this function.</p></td></tr>
198*91df013fSAsim Jamshed</table>
199*91df013fSAsim Jamshed
200*91df013fSAsim Jamshed<h2>AUTHORS
201*91df013fSAsim Jamshed<a name="AUTHORS"></a>
202*91df013fSAsim Jamshed</h2>
203*91df013fSAsim Jamshed
204*91df013fSAsim Jamshed
205*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">mOS development
206*91df013fSAsim Jamshedteam &lt;[email protected]&gt;</p>
207*91df013fSAsim Jamshed
208*91df013fSAsim Jamshed<h2>SEE ALSO
209*91df013fSAsim Jamshed<a name="SEE ALSO"></a>
210*91df013fSAsim Jamshed</h2>
211*91df013fSAsim Jamshed
212*91df013fSAsim Jamshed
213*91df013fSAsim Jamshed
214*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em"><b>mtcp_peek</b>(),
215*91df013fSAsim Jamshed<b>mtcp_socket</b>(),</p>
216*91df013fSAsim Jamshed
217*91df013fSAsim Jamshed<h2>COLOPHON
218*91df013fSAsim Jamshed<a name="COLOPHON"></a>
219*91df013fSAsim Jamshed</h2>
220*91df013fSAsim Jamshed
221*91df013fSAsim Jamshed
222*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">This page is
223*91df013fSAsim Jamshedpart of mOS release 0.3 <i>docs</i> section. A description
224*91df013fSAsim Jamshedof the project, and information about reporting bugs, can be
225*91df013fSAsim Jamshedfound at http://mos.kaist.edu/.</p>
226*91df013fSAsim Jamshed<hr>
227*91df013fSAsim Jamshed</body>
228*91df013fSAsim Jamshed</html>
229