[MacPorts] #42152: libbiosig: fails to build on snow leopard (Undefined symbols: _getline)

[MacPorts]

#42152: libbiosig: fails to build on snow leopard (Undefined symbols: _getline)
------------------------+---------------------------------------
  Reporter:  mojca@…    |      Owner:  christsc@…
      Type:  defect     |     Status:  new
  Priority:  Normal     |  Milestone:
 Component:  ports      |    Version:
Resolution:             |   Keywords:  snowleopard leopard tiger
      Port:  libbiosig  |
------------------------+---------------------------------------

Comment (by mojca@…):

 Before I commit anything: can you please explain me how the patch works?

 What does the following do?
 {{{
 COMMAND ${GAWK} -f annotatedECG.awk extern/11073-10102-AnnexB.txt >
 "11073-10102-AnnexB.i"
 }}}
 and why is
 {{{
 #ifdef MACPORTS
 }}}
 needed? What does `#include <unistd.h>` do and where does that file come
 from? `/usr/include/unistd.h` or from `/opt/local/sowhere/else`?

 I can commit it nonetheless, but I would like to roughly understand what
 I'm doing.

-- 
Ticket URL: <https://trac.macports.org/ticket/42152#comment:14>
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