Updates for Big Sur.

go.mod

@@ -0,0 +1,3 @@
+module git.wow.st/gmp/clip
+
+go 1.16

ns/pasteboard.go

@@ -191,7 +191,7 @@ func (o *NSPasteboard) ClearContents() {
 
 func (o *NSPasteboard) SetString(s string) bool {
 	string := NSStringWithGoString(s)
-        ret := (C.NSPasteboard_inst_SetString(o.Ptr(), string.Ptr())) != 0
+        ret := (C.NSPasteboard_inst_SetString(o.Ptr(), string.Ptr())) != false
         runtime.KeepAlive(o)
 	runtime.KeepAlive(string)
         return ret

nswrap.yaml

@@ -1,7 +1,7 @@
 # binding generator for git.wow.st/gmp/nswrap
 # original binding is in ns/main.go- and is not used.
 inputfiles:
-    - /System/Library/Frameworks/AppKit.framework/Headers/NSPasteboard.h
+    - /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/AppKit.framework/Headers/NSPasteboard.h
 classes:
     - NSPasteboard
     - NSString