Hi Simon, > > | native fd | gnulib | native SOCKET | > > | | wrapped fd | | > > ----------------------------------------------------------------------- > > ReadFile, WriteFile | | | YES | > > ----------------------------------------------------------------------- > > MSVCRT recv, send | | | YES | > > ----------------------------------------------------------------------- > > MSVCRT read, write | YES | YES | | > > ----------------------------------------------------------------------- > > Thanks. Is there a place in the gnulib manual to add this?
The contents of this matrix can be summarized in two sentences: - 'int fd' and SOCKET are different data types. - SOCKETs are HANDLEs and can be used with ReadFile and WriteFile. - 'int fd' can be used with POSIX functions like read() and write(). But feel free to augment the doc. > I searched for your _WIN32/CYGWIN/etc CPP macro matrix yesterday, and > having that in the gnulib manual as well would have saved me time. The reference for this ought to be http://predef.sourceforge.net/, but if you want to write something about it in the gnulib doc, then: - The test whether native Win32 API is available is (defined _WIN32 || defined __WIN32__). Which of the two symbols is defined, depends on the compiler. - Cygwin is a POSIX implementation on which the Win32 API is _optionally_ available. On Cygwin, this expression may evaluate to true or false, depending whether the developer wants to compile his programs in such a way that they can access Win32 API or not. - For POSIX functionality that is already implemented in Cygwin, there is no need to use the Win32 API, therefore here we use the conditional (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__. - For access to Win32 functionality that has no overlap with POSIX, the right conditional is (defined _WIN32 || defined __WIN32__). Bruno
