1*91df013fSAsim Jamshed<!-- Creator : groff version 1.22.2 --> 2*91df013fSAsim Jamshed<!-- CreationDate: Wed Feb 1 23:55:12 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_recv</title> 17*91df013fSAsim Jamshed 18*91df013fSAsim Jamshed</head> 19*91df013fSAsim Jamshed<body> 20*91df013fSAsim Jamshed 21*91df013fSAsim Jamshed<h1 align="center">mtcp_recv</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_recv 41*91df013fSAsim Jamshed− receive a message from a socket</p> 42*91df013fSAsim Jamshed 43*91df013fSAsim Jamshed<h2>SYNOPSIS 44*91df013fSAsim Jamshed<a name="SYNOPSIS"></a> 45*91df013fSAsim Jamshed</h2> 46*91df013fSAsim Jamshed 47*91df013fSAsim Jamshed 48*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em"><b>#include 49*91df013fSAsim Jamshed<mtcp_api.h></b></p> 50*91df013fSAsim Jamshed 51*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em"><b>ssize_t 52*91df013fSAsim Jamshedmtcp_recv(mctx_t</b> <i>mctx</i><b>, int</b> 53*91df013fSAsim Jamshed<i>sockid</i><b>, char *</b><i>buf</i><b>, size_t</b> 54*91df013fSAsim Jamshed<i>len</i><b>, int</b> <i>flags</i><b>);</b></p> 55*91df013fSAsim Jamshed 56*91df013fSAsim Jamshed<h2>DESCRIPTION 57*91df013fSAsim Jamshed<a name="DESCRIPTION"></a> 58*91df013fSAsim Jamshed</h2> 59*91df013fSAsim Jamshed 60*91df013fSAsim Jamshed 61*91df013fSAsim Jamshed 62*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em"><b>mtcp_recv</b>() 63*91df013fSAsim Jamshedcall is normally used only on a <i>connected</i> socket (see 64*91df013fSAsim Jamshed<b>mtcp_connect()</b>) and is identical to 65*91df013fSAsim Jamshed<b>mtcp_read()</b> with <i>flags</i> value set to 0. The 66*91df013fSAsim Jamshedfunction can be used to read up to <i>len</i> number of 67*91df013fSAsim Jamshedbytes from mTCP socket via socket descriptor <i>sockid</i> 68*91df013fSAsim Jamshedinto the buffer starting at <i>buf.</i> It is the 69*91df013fSAsim Jamshedresponsibility of the user to allocate memory for <i>buf</i> 70*91df013fSAsim Jamshedarray.</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_recv()</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">An 79*91df013fSAsim Jamshed<b>mtcp_recv</b>() call takes an additional argument named 80*91df013fSAsim Jamshed<i>mctx</i> that represents the per-core mTCP context in an 81*91df013fSAsim Jamshedapplication (see <b>mtcp_create_context()</b> for 82*91df013fSAsim Jamsheddetails).</p> 83*91df013fSAsim Jamshed 84*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">The 85*91df013fSAsim Jamshed<i>flags</i> argument to a <b>mtcp_recv()</b> call currently 86*91df013fSAsim Jamshedaccepts only one non-zero value:</p> 87*91df013fSAsim Jamshed 88*91df013fSAsim Jamshed<table width="100%" border="0" rules="none" frame="void" 89*91df013fSAsim Jamshed cellspacing="0" cellpadding="0"> 90*91df013fSAsim Jamshed<tr valign="top" align="left"> 91*91df013fSAsim Jamshed<td width="11%"></td> 92*91df013fSAsim Jamshed<td width="12%"> 93*91df013fSAsim Jamshed 94*91df013fSAsim Jamshed 95*91df013fSAsim Jamshed<p><b>MSG_PEEK</b></p></td> 96*91df013fSAsim Jamshed<td width="3%"></td> 97*91df013fSAsim Jamshed<td width="74%"> 98*91df013fSAsim Jamshed 99*91df013fSAsim Jamshed 100*91df013fSAsim Jamshed<p>This flag causes the receive operation to return data 101*91df013fSAsim Jamshedfrom the beginning of the receive queue without removing 102*91df013fSAsim Jamshedthat data from the queue. Thus, a subsequent receive call 103*91df013fSAsim Jamshedwill return the same data.</p></td></tr> 104*91df013fSAsim Jamshed</table> 105*91df013fSAsim Jamshed 106*91df013fSAsim Jamshed<h2>RETURN VALUE 107*91df013fSAsim Jamshed<a name="RETURN VALUE"></a> 108*91df013fSAsim Jamshed</h2> 109*91df013fSAsim Jamshed 110*91df013fSAsim Jamshed 111*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">On success, the 112*91df013fSAsim Jamshednumber of bytes read is returned. It is not an error if this 113*91df013fSAsim Jamshednumber is smaller than the number of bytes requested; this 114*91df013fSAsim Jamshedmay happen when the socket has fewer number of bytes 115*91df013fSAsim Jamshedbuffered at that moment. On all errors, -1 is returned and 116*91df013fSAsim Jamshed<i>errno</i> is set appropriately.</p> 117*91df013fSAsim Jamshed 118*91df013fSAsim Jamshed<h2>ERRORS 119*91df013fSAsim Jamshed<a name="ERRORS"></a> 120*91df013fSAsim Jamshed</h2> 121*91df013fSAsim Jamshed 122*91df013fSAsim Jamshed 123*91df013fSAsim Jamshed<table width="100%" border="0" rules="none" frame="void" 124*91df013fSAsim Jamshed cellspacing="0" cellpadding="0"> 125*91df013fSAsim Jamshed<tr valign="top" align="left"> 126*91df013fSAsim Jamshed<td width="11%"></td> 127*91df013fSAsim Jamshed<td width="12%"> 128*91df013fSAsim Jamshed 129*91df013fSAsim Jamshed 130*91df013fSAsim Jamshed<p style="margin-top: 1em"><b>EBADF</b></p></td> 131*91df013fSAsim Jamshed<td width="3%"></td> 132*91df013fSAsim Jamshed<td width="74%"> 133*91df013fSAsim Jamshed 134*91df013fSAsim Jamshed 135*91df013fSAsim Jamshed<p style="margin-top: 1em">The socket descriptor 136*91df013fSAsim Jamshed<i>sockid</i> is invalid.</p></td></tr> 137*91df013fSAsim Jamshed<tr valign="top" align="left"> 138*91df013fSAsim Jamshed<td width="11%"></td> 139*91df013fSAsim Jamshed<td width="12%"> 140*91df013fSAsim Jamshed 141*91df013fSAsim Jamshed 142*91df013fSAsim Jamshed<p><b>EINVAL</b></p></td> 143*91df013fSAsim Jamshed<td width="3%"></td> 144*91df013fSAsim Jamshed<td width="74%"> 145*91df013fSAsim Jamshed 146*91df013fSAsim Jamshed 147*91df013fSAsim Jamshed<p>Invalid argument passed.</p></td></tr> 148*91df013fSAsim Jamshed<tr valign="top" align="left"> 149*91df013fSAsim Jamshed<td width="11%"></td> 150*91df013fSAsim Jamshed<td width="12%"> 151*91df013fSAsim Jamshed 152*91df013fSAsim Jamshed 153*91df013fSAsim Jamshed<p><b>ENOTSOCK</b></p></td> 154*91df013fSAsim Jamshed<td width="3%"></td> 155*91df013fSAsim Jamshed<td width="74%"> 156*91df013fSAsim Jamshed 157*91df013fSAsim Jamshed 158*91df013fSAsim Jamshed<p>The socket referred to by <i>sockid</i> has invalid 159*91df013fSAsim Jamshed<i>type</i></p> </td></tr> 160*91df013fSAsim Jamshed<tr valign="top" align="left"> 161*91df013fSAsim Jamshed<td width="11%"></td> 162*91df013fSAsim Jamshed<td width="12%"> 163*91df013fSAsim Jamshed 164*91df013fSAsim Jamshed 165*91df013fSAsim Jamshed<p><b>ENOTCONN</b></p></td> 166*91df013fSAsim Jamshed<td width="3%"></td> 167*91df013fSAsim Jamshed<td width="74%"> 168*91df013fSAsim Jamshed 169*91df013fSAsim Jamshed 170*91df013fSAsim Jamshed<p>Th socket referred to by <i>sockid</i> is in a TCP state 171*91df013fSAsim Jamshedthat disallows read operations.</p></td></tr> 172*91df013fSAsim Jamshed<tr valign="top" align="left"> 173*91df013fSAsim Jamshed<td width="11%"></td> 174*91df013fSAsim Jamshed<td width="12%"> 175*91df013fSAsim Jamshed 176*91df013fSAsim Jamshed 177*91df013fSAsim Jamshed<p><b>EAGAIN</b></p></td> 178*91df013fSAsim Jamshed<td width="3%"></td> 179*91df013fSAsim Jamshed<td width="74%"> 180*91df013fSAsim Jamshed 181*91df013fSAsim Jamshed 182*91df013fSAsim Jamshed<p>The socket referred to by <i>sockid</i> does not have 183*91df013fSAsim Jamshedany available bytes in its buffer for reading.</p></td></tr> 184*91df013fSAsim Jamshed</table> 185*91df013fSAsim Jamshed 186*91df013fSAsim Jamshed<h2>AUTHORS 187*91df013fSAsim Jamshed<a name="AUTHORS"></a> 188*91df013fSAsim Jamshed</h2> 189*91df013fSAsim Jamshed 190*91df013fSAsim Jamshed 191*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">mOS development 192*91df013fSAsim Jamshedteam <[email protected]></p> 193*91df013fSAsim Jamshed 194*91df013fSAsim Jamshed<h2>SEE ALSO 195*91df013fSAsim Jamshed<a name="SEE ALSO"></a> 196*91df013fSAsim Jamshed</h2> 197*91df013fSAsim Jamshed 198*91df013fSAsim Jamshed 199*91df013fSAsim Jamshed 200*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em"><b>mtcp_bind</b>(), 201*91df013fSAsim Jamshed<b>mtcp_read</b>(), <b>mtcp_accept</b>(), 202*91df013fSAsim Jamshed<b>mtcp_connect</b>(), <b>mtcp_socket</b>(), 203*91df013fSAsim Jamshed<b>mtcp_write</b>()</p> 204*91df013fSAsim Jamshed 205*91df013fSAsim Jamshed<h2>COLOPHON 206*91df013fSAsim Jamshed<a name="COLOPHON"></a> 207*91df013fSAsim Jamshed</h2> 208*91df013fSAsim Jamshed 209*91df013fSAsim Jamshed 210*91df013fSAsim Jamshed<p style="margin-left:11%; margin-top: 1em">This page is 211*91df013fSAsim Jamshedpart of mOS release 0.3 <i>docs</i> section. A description 212*91df013fSAsim Jamshedof the project, and information about reporting bugs, can be 213*91df013fSAsim Jamshedfound at http://mos.kaist.edu/.</p> 214*91df013fSAsim Jamshed<hr> 215*91df013fSAsim Jamshed</body> 216*91df013fSAsim Jamshed</html> 217