How do I tell whether my cygwin installation is 32 or 64 bit?

Question

How do I tell whether my cygwin installation is 32 or 64 bit? I don\'t remember which setup.exe to download. And I would hate to mess up my cygwin installation.

Answer 1

NateT gives the correct command to "print the machine hardware name" according to "uname --help":

uname -m

I get "x86_64" or "i686", but who knows whether those strings will change? Here's the entire output of "uname -a". The WOW64 tells you it's 32-bit Cygwin on 64-bit Windows. On 32-bit you've got no choice, right? ; - )

$ uname -a
CYGWIN_NT-6.1-WOW64 Pegasus 1.7.32(0.274/5/3) 2014-08-13 23:03 i686 Cygwin

Update: (Thanks to theDrake.) Ironically, since around Feb 2015 the WOW64 in the string has changed to WOW, so although checking for WOW is probably safe now it seems the "machine hardware name" might indeed be safer than the "kernel name".

Cygwin does seem to be take backwards compatibility seriously according to that thread, but also note that under MSYS2 you'd need to rely on the "machine hardware name" anyway and not the "kernel name":

$ uname -a
MSYS_NT-6.1 Pegasus 2.5.0(0.295/5/3) 2016-03-15 11:29 x86_64 Msys