MinGW does not natively support the POSIX sleep() function so we have
had an override that was a part of the GR_PWIN32 macro and included in
the generated config.h file. When compiling for Windows on POSIX using
MinGW, Autotools will detect sleep() and set HAVE_SLEEP which prevented
the substitution from being included in the source. Adding a test for
_WIN32 (set by MinGW's gcc) then caused a warning from src/network.c on
POSIX about winsock2.h needing to be included before windows.h. As
config.h needed to be included first, the solution to break out the
substitution that includes windows.h into its own file. This patch
provides that solution and allows the code to compile cleanly on POSIX,
using MinGW on both POSIX and Windows, and on Cygwin.
Building libltdl recursively with MinGW failed with an error of "sleep"
being redefined. Commenting out the sleep() definition in config.h.in
resulted in libtdl compiling but a linker failure in libyaesu as
"_sleep" was not defined.
A bit of searching reveals that the MS Windows API does not include
"sleep" and MinGW does not include it either, hence the definition in
gr_pwin32.m4 from the GNU Radio project. Uopn finding a MinGW User
thread from 2007 that discussed this very issue, the following message
hinted that using a CPP #define to wrap Windows Sleep() may work:
http://mingw.5.n7.nabble.com/Help-where-is-the-C-language-sleep-function-tp8921p8925.html
And indeed it seems to. Compilation is now clean with recursive libltdl
and the rest of Hamlib, but does it work?
Using the -Wall switch to autoconf/autoreconf revealed a number of
obsolete macros. At the moment, offending macros have been commented
out using 'dnl'. They will be removed at some later date.
Mike Black W9MDB