Bug #12987: Win32 API.rb can not call function without argument.

• Status: Closed
• Assignee: -
• Target version: -
• Backport: 2.1: WONTFIX, 2.2: REQUIRED, 2.3: REQUIRED
• Tags: ext, win, notbug

[katonbo (Masahiro Kitajima)]

In Win32API.rb, it is not possible to call a function without arguments.
I could avoid it for the time being if I did the following (against trunk).

diff --git a/ext/win32/lib/Win32API.rb b/ext/win32/lib/Win32API.rb
index d03ecc1..946be3e 100644
--- a/ext/win32/lib/Win32API.rb
+++ b/ext/win32/lib/Win32API.rb
@@ -17,6 +17,7 @@ class Win32API
   def initialize(dllname, func, import, export = "0", calltype = :stdcall)
     @proto = [import].join.tr(WIN32_TYPES, DL_TYPES).sub(/^(.)0*$/, '\1')
     import = @proto.chars.map {|win_type| TYPEMAP[win_type.tr(WIN32_TYPES, DL_T
+    @proto = "" if @proto == "0"
     export = TYPEMAP[export.tr(WIN32_TYPES, DL_TYPES)]
     calltype = Fiddle::Importer.const_get(:CALL_TYPE_TO_ABI)[calltype]

[usa (Usaku NAKAMURA)]

For workaround, you can use '' instead of '0'.

[usa (Usaku NAKAMURA)]

• Backport changed from 2.1: UNKNOWN, 2.2: UNKNOWN, 2.3: UNKNOWN to 2.1: WONTFIX, 2.2: REQUIRED, 2.3: REQUIRED

[katonbo (Masahiro Kitajima)]

Thank you very much.
I just learned that only nil was clearly stating that there are no arguments in the previous document.
I used a single 'V' to specify no arguments, so it was up to this idea.

[jeremyevans0 (Jeremy Evans)]

• Status changed from Open to Closed

I tried with ruby 2.6.3p62 (2019-04-16 revision 67580) [i386-mingw32] and ruby 1.9.3p551 (2014-11-13) [i386-mingw32] and was able to call a function without an argument:

require 'Win32API'
getch = Win32API.new("C:\\Windows\\SysWOW64\\crtdll.dll", "_getch", [], 'L')
getch.Call
# => 97

So I think this can be closed.