#493 fopen fails to create a file if mode wbx is used

[John Doe]

The file in question doesn't exist. There aren't any permission problems.

Using:
gcc (i686-posix-dwarf-rev0, Built by MinGW-W64 project) 5.1.0
Windows 7, SP1 , 32-bit

Please check.

( If the mode is wb or w, then the file gets created. )