"win32" vs "win64" for osgi.os property

Question

I have Win7 64 bit OS on my machine. I was working on creating a 64 bit plugin in eclipse. I was trying to set value for osgi.os property. I referred this link.

The link mentions

Property    Meaning                   Possible values
osgi.os     operating system          win32, win32, linux, macosx, aix, solaris, hpux, qnx
osgi.ws     windowing system          win32, motif, gtk, photon, carbon
osgi.arch   processor architecture    x86, x86_64, ia64, ia64_32, ppc, PA_RISC, sparc

I was wondering for osgi.os options it has no mention for win64 as a possible value. If I have win64 OS in my machine what value should I assign to property osgi.os as it only shows win32 as possible values for osgi.os property?

And for osgi.os property why does it repeats win32 twice as possible values? For osgi.os property are there any reason behind mentioning win32, win32 twice instead of just mentioning win32 only once?

Answer 1

Windows is usually referred to as "Win32" to distinguish it from the old 16 bit Windows 3.1. The "Win32 API" is the name of the native API. Whether the OS and apps are built for 32 bit or 64 bit, it's all still Win32.

In the above table it looks like the osgi.arch property will determine whether your plugin is built for 32 bit or 64 bit. Set it to x86 for 32 bit, and x86_64 for 64 bit. The other two fields should both be set to win32.

I would guess that mentioning it twice for os is a mistake.