docs/rmr_get_src.3.rst

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============================================================================================
Man Page: rmr_get_src
============================================================================================




RMR LIBRARY FUNCTIONS
=====================



NAME
----

rmr_get_src


SYNOPSIS
--------


::

  #include <rmr/rmr.h>

  unsigned char* rmr_get_src( rmr_mbuf_t* mbuf, unsigned char* dest )



DESCRIPTION
-----------

The ``rmr_get_src`` function will copy the *source*
information from the message to a buffer (dest) supplied by
the user. In an RMR message, the source is the sender's
information that is used for return to sender function calls,
and is generally the hostname and port in the form *name*.
The source might be an IP address port combination; the data
is populated by the sending process and the only requirement
is that it be capable of being used to start a TCP session
with the sender.

The maximum size allowed by RMR is 64 bytes (including the
nil string terminator), so the user must ensure that the
destination buffer given is at least 64 bytes.


RETURN VALUE
------------

On success, a pointer to the destination buffer is given as a
convenience to the user programme. On failure, a nil pointer
is returned and the value of errno is set.


ERRORS
------

If an error occurs, the value of the global variable
``errno`` will be set to one of the following with the
indicated meaning.

    .. list-table::
      :widths: auto
      :header-rows: 0
      :class: borderless

      * - **EINVAL**
        -
          The message, or an internal portion of the message, was
          corrupted or the pointer was invalid.




SEE ALSO
--------

rmr_alloc_msg(3), rmr_bytes2xact(3), rmr_bytes2meid(3),
rmr_call(3), rmr_free_msg(3), rmr_get_rcvfd(3),
rmr_get_srcip(3), rmr_payload_size(3), rmr_send_msg(3),
rmr_rcv_msg(3), rmr_rcv_specific(3), rmr_rts_msg(3),
rmr_ready(3), rmr_fib(3), rmr_has_str(3), rmr_tokenise(3),
rmr_mk_ring(3), rmr_ring_free(3), rmr_str2meid(3),
rmr_str2xact(3), rmr_wh_open(3), rmr_wh_send_msg(3)