MessageBox for Windows command line.
Redistributable x86 packages [https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170] are required to run the program
@echo|set /p="@set mytmp=">1.bat\
@messagebox -message "yes or no" -button yesno>>1.bat\
@echo errorlevel=%errorlevel%\
@call 1.bat\
@echo output=%mytmp%