docs/rmr_get_srcip.3.rst

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============================================================================================
Man Page: rmr_get_srcip
============================================================================================




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



NAME
----

rmr_get_srcip


SYNOPSIS
--------


::

  #include <rmr/rmr.h>

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



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

The ``rmr_get_srcip`` function will copy the *source IP
address* from the message to a buffer (dest) supplied by the
user. In an RMR message, the source IP address is the
sender's information that is used for return to sender
function calls; this function makes it available to the user
application. The address is maintained as IP:port where *IP*
could be either an IPv6 or IPv4 address depending on what was
provided by the sending application.

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. The user
application should use the RMR constant RMR_MAX_SRC to ensure
that the buffer supplied is large enough, and to protect
against future RMR enhancements which might increase the
address buffer size requirement.


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_src(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)