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'\" t
.\"     Title: zmq_msg_init
.\"    Author: [see the "AUTHORS" section]
.\" Generator: DocBook XSL Stylesheets v1.75.2 <http://docbook.sf.net/>
.\"      Date: 04/04/2012
.\"    Manual: 0MQ Manual
.\"    Source: 0MQ 2.2.0
.\"  Language: English
.\"
.TH "ZMQ_MSG_INIT" "3" "04/04/2012" "0MQ 2\&.2\&.0" "0MQ Manual"
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.SH "NAME"
zmq_msg_init \- initialise empty 0MQ message
.SH "SYNOPSIS"
.sp
\fBint zmq_msg_init (zmq_msg_t \fR\fB\fI*msg\fR\fR\fB);\fR
.SH "DESCRIPTION"
.sp
The \fIzmq_msg_init()\fR function shall initialise the message object referenced by \fImsg\fR to represent an empty message\&. This function is most useful when called before receiving a message with \fIzmq_recv()\fR\&.
.if n \{\
.sp
.\}
.RS 4
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBCaution\fR
.ps -1
.br
.sp
Never access \fIzmq_msg_t\fR members directly, instead always use the \fIzmq_msg\fR family of functions\&.
.sp .5v
.RE
.if n \{\
.sp
.\}
.RS 4
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBCaution\fR
.ps -1
.br
.sp
The functions \fIzmq_msg_init()\fR, \fIzmq_msg_init_data()\fR and \fIzmq_msg_init_size()\fR are mutually exclusive\&. Never initialize the same \fIzmq_msg_t\fR twice\&.
.sp .5v
.RE
.SH "RETURN VALUE"
.sp
The \fIzmq_msg_init()\fR function shall return zero if successful\&. Otherwise it shall return \-1 and set \fIerrno\fR to one of the values defined below\&.
.SH "ERRORS"
.sp
No errors are defined\&.
.SH "EXAMPLE"
.PP
\fBReceiving a message from a socket\fR. 
.sp
.if n \{\
.RS 4
.\}
.nf
zmq_msg_t msg;
rc = zmq_msg_init (&msg);
assert (rc == 0);
rc = zmq_recv (socket, &msg, 0);
assert (rc == 0);
.fi
.if n \{\
.RE
.\}
.sp
.SH "SEE ALSO"
.sp
\fBzmq_msg_init_size\fR(3) \fBzmq_msg_init_data\fR(3) \fBzmq_msg_close\fR(3) \fBzmq_msg_data\fR(3) \fBzmq_msg_size\fR(3) \fBzmq\fR(7)
.SH "AUTHORS"
.sp
This manual page was written by the 0MQ community\&.