README.developer states
Don't include <unistd.h> without protecting it with
#ifdef HAVE_UNISTD_H
...
#endif
and, if you're including it to get routines such as "open()", "close()",
"read()", and "write()" declared, also include <io.h> if present:
#ifdef HAVE_IO_H
#include <io.h>
#endif
so looking at io.h, it's included by 5 files, only one of which (ascend_scanner.c) adds the HAVE_IO_H guard, all the others use a _WIN32 guard.
ConfigureChecks.cmake doesn't run a check for io.h, and
cmakeconfig.h.in doesn't have a #cmakdefine for HAVE_IO_H.
What's the best way to make this all consistent, fix CMake and the _WIN32 guards to use HAVE_IO_H, or change the docs and ascend_scanner to use _WIN32?
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