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* Problem: boilerplate when init msg from data copy Solution: Add zmq_msg_init_buffer to construct a message by copying memory from buffer.
73 lines
1.7 KiB
Plaintext
73 lines
1.7 KiB
Plaintext
zmq_msg_copy(3)
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===============
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NAME
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----
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zmq_msg_copy - copy content of a message to another message
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SYNOPSIS
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--------
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*int zmq_msg_copy (zmq_msg_t '*dest', zmq_msg_t '*src');*
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DESCRIPTION
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-----------
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The _zmq_msg_copy()_ function shall copy the message object referenced by 'src'
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to the message object referenced by 'dest'. The original content of 'dest', if
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any, shall be released. You must initialise 'dest' before copying to it.
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CAUTION: The implementation may choose not to physically copy the message
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content, rather to share the underlying buffer between 'src' and 'dest'. Avoid
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modifying message content after a message has been copied with
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_zmq_msg_copy()_, doing so can result in undefined behaviour. If what you need
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is an actual hard copy, initialize a new message using _zmq_msg_init_buffer()_
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with the message content.
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CAUTION: Never access 'zmq_msg_t' members directly, instead always use the
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_zmq_msg_ family of functions.
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RETURN VALUE
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------------
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The _zmq_msg_copy()_ function shall return zero if successful. Otherwise it
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shall return `-1` and set 'errno' to one of the values defined below.
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ERRORS
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------
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*EFAULT*::
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Invalid message.
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EXAMPLE
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-------
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.Copying a message
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----
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zmq_msg_t msg;
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zmq_msg_init_buffer (&msg, "Hello, World", 12);
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zmq_msg_t copy;
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zmq_msg_init (©);
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zmq_msg_copy (©, &msg);
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...
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zmq_msg_close (©);
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zmq_msg_close (&msg);
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----
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SEE ALSO
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--------
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linkzmq:zmq_msg_move[3]
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linkzmq:zmq_msg_init[3]
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linkzmq:zmq_msg_init_size[3]
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linkzmq:zmq_msg_init_buffer[3]
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linkzmq:zmq_msg_init_data[3]
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linkzmq:zmq_msg_close[3]
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linkzmq:zmq[7]
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AUTHORS
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-------
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This page was written by the 0MQ community. To make a change please
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read the 0MQ Contribution Policy at <http://www.zeromq.org/docs:contributing>.
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