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- nn_allocmsg(3)
- ==============
- NAME
- ----
- nn_allocmsg - allocate a message
- SYNOPSIS
- --------
- *#include <nanomsg/nn.h>*
- *void *nn_allocmsg (size_t 'size', int 'type');*
- DESCRIPTION
- -----------
- Allocate a message of the specified 'size' to be sent in zero-copy fashion.
- The content of the message is undefined after allocation and it should be filled
- in by the user. While <<nn_send#,nn_send(3)>> and <<nn_sendmsg#,nn_sendmsg(3)>> allow
- to send arbitrary buffers, buffers allocated using _nn_allocmsg()_ can be more
- efficient for large messages as they allow for using zero-copy techniques.
- 'type' parameter specifies type of allocation mechanism to use. Zero is the
- default one, however, individual transport mechanisms may define their
- own allocation mechanisms, such as allocating in shared memory or allocating
- a memory block pinned down to a physical memory address. Such allocation,
- when used with the transport that defines them, should be more efficient
- than the default allocation mechanism.
- RETURN VALUE
- ------------
- If the function succeeds pointer to newly allocated buffer is returned.
- Otherwise, NULL is returned and 'errno' is set to to one of the values
- defined below.
- ERRORS
- ------
- *EINVAL*::
- Supplied allocation 'type' is invalid.
- *ENOMEM*::
- Not enough memory to allocate the message.
- EXAMPLE
- -------
- ----
- void *buf = nn_allocmsg (12, 0);
- memcpy (buf, "Hello world!", 12);
- nn_send (s, &buf, NN_MSG, 0);
- ----
- SEE ALSO
- --------
- <<nn_freemsg#,nn_freemsg(3)>>
- <<nn_reallocmsg#,nn_reallocmsg(3)>>
- <<nn_send#,nn_send(3)>>
- <<nn_sendmsg#,nn_sendmsg(3)>>
- <<nanomsg#,nanomsg(7)>>
- AUTHORS
- -------
- link:mailto:sustrik@250bpm.com[Martin Sustrik]
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