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Diffstat (limited to 'doc/zmq_msg_init_data.3')
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diff --git a/doc/zmq_msg_init_data.3 b/doc/zmq_msg_init_data.3 new file mode 100644 index 0000000..76ef4b7 --- /dev/null +++ b/doc/zmq_msg_init_data.3 @@ -0,0 +1,130 @@ +'\" t +.\" Title: zmq_msg_init_data +.\" Author: [see the "AUTHORS" section] +.\" Generator: DocBook XSL Stylesheets v1.76.1 <http://docbook.sf.net/> +.\" Date: 10/14/2014 +.\" Manual: 0MQ Manual +.\" Source: 0MQ 4.0.5 +.\" Language: English +.\" +.TH "ZMQ_MSG_INIT_DATA" "3" "10/14/2014" "0MQ 4\&.0\&.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 +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[]\&. |