You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
147 lines
4.1 KiB
147 lines
4.1 KiB
6 years ago
|
'\" t
|
||
|
|
.\" Title: zmq_msg_init_data
|
||
|
|
.\" Author: [see the "AUTHORS" section]
|
||
|
|
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
|
||
|
|
.\" Date: 09/14/2016
|
||
|
|
.\" Manual: 0MQ Manual
|
||
|
|
.\" Source: 0MQ 4.1.5
|
||
|
|
.\" Language: English
|
||
|
|
.\"
|
||
|
|
.TH "ZMQ_MSG_INIT_DATA" "3" "09/14/2016" "0MQ 4\&.1\&.5" "0MQ Manual"
|
||
|
|
.\" -----------------------------------------------------------------
|
||
|
|
.\" * Define some portability stuff
|
||
|
|
.\" -----------------------------------------------------------------
|
||
|
|
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
|
.\" http://bugs.debian.org/507673
|
||
|
|
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
|
||
|
|
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
|
.ie \n(.g .ds Aq \(aq
|
||
|
|
.el .ds Aq '
|
||
|
|
.\" -----------------------------------------------------------------
|
||
|
|
.\" * set default formatting
|
||
|
|
.\" -----------------------------------------------------------------
|
||
|
|
.\" disable hyphenation
|
||
|
|
.nh
|
||
|
|
.\" disable justification (adjust text to left margin only)
|
||
|
|
.ad l
|
||
|
|
.\" -----------------------------------------------------------------
|
||
|
|
.\" * MAIN CONTENT STARTS HERE *
|
||
|
|
.\" -----------------------------------------------------------------
|
||
|
|
.SH "NAME"
|
||
|
|
zmq_msg_init_data \- initialise 0MQ message from a supplied buffer
|
||
|
|
.SH "SYNOPSIS"
|
||
|
|
.sp
|
||
|
|
\fBtypedef void (zmq_free_fn) (void \fR\fB\fI*data\fR\fR\fB, void \fR\fB\fI*hint\fR\fR\fB);\fR
|
||
|
|
.sp
|
||
|
|
\fBint zmq_msg_init_data (zmq_msg_t \fR\fB\fI*msg\fR\fR\fB, void \fR\fB\fI*data\fR\fR\fB, size_t \fR\fB\fIsize\fR\fR\fB, zmq_free_fn \fR\fB\fI*ffn\fR\fR\fB, void \fR\fB\fI*hint\fR\fR\fB);\fR
|
||
|
|
.SH "DESCRIPTION"
|
||
|
|
.sp
|
||
|
|
The \fIzmq_msg_init_data()\fR function shall initialise the message object referenced by \fImsg\fR to represent the content referenced by the buffer located at address \fIdata\fR, \fIsize\fR bytes long\&. No copy of \fIdata\fR shall be performed and 0MQ shall take ownership of the supplied buffer\&.
|
||
|
|
.sp
|
||
|
|
If provided, the deallocation function \fIffn\fR shall be called once the data buffer is no longer required by 0MQ, with the \fIdata\fR and \fIhint\fR arguments supplied to \fIzmq_msg_init_data()\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 deallocation function \fIffn\fR needs to be thread\-safe, since it will be called from an arbitrary thread\&.
|
||
|
|
.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
|
||
|
|
If the deallocation function is not provided, the allocated memory will not be freed, and this may cause a memory leak\&.
|
||
|
|
.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_data()\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"
|
||
|
|
.PP
|
||
|
|
\fBENOMEM\fR
|
||
|
|
.RS 4
|
||
|
|
Insufficient storage space is available\&.
|
||
|
|
.RE
|
||
|
|
.SH "EXAMPLE"
|
||
|
|
.PP
|
||
|
|
\fBInitialising a message from a supplied buffer\fR.
|
||
|
|
.sp
|
||
|
|
.if n \{\
|
||
|
|
.RS 4
|
||
|
|
.\}
|
||
|
|
.nf
|
||
|
|
void my_free (void *data, void *hint)
|
||
|
|
{
|
||
|
|
free (data);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* \&.\&.\&. */
|
||
|
|
|
||
|
|
void *data = malloc (6);
|
||
|
|
assert (data);
|
||
|
|
memcpy (data, "ABCDEF", 6);
|
||
|
|
zmq_msg_t msg;
|
||
|
|
rc = zmq_msg_init_data (&msg, data, 6, my_free, NULL);
|
||
|
|
assert (rc == 0);
|
||
|
|
.fi
|
||
|
|
.if n \{\
|
||
|
|
.RE
|
||
|
|
.\}
|
||
|
|
.sp
|
||
|
|
.SH "SEE ALSO"
|
||
|
|
.sp
|
||
|
|
\fBzmq_msg_init_size\fR(3) \fBzmq_msg_init\fR(3) \fBzmq_msg_close\fR(3) \fBzmq_msg_data\fR(3) \fBzmq_msg_size\fR(3) \fBzmq\fR(7)
|
||
|
|
.SH "AUTHORS"
|
||
|
|
.sp
|
||
|
|
This page was written by the 0MQ community\&. To make a change please read the 0MQ Contribution Policy at \m[blue]\fBhttp://www\&.zeromq\&.org/docs:contributing\fR\m[]\&.
|