The Slick-C code below will not run. However, if Typora.exe is in my PATH, the commented line below works. Why can't Slick-C find 'C:\Program Files\Typora\Typora.exe'? I've tried numerous variations. What am I missing?
#include "slick.sh"
_command void runtypora() name_info(','VSARG2_READ_ONLY|VSARG2_REQUIRES_EDITORCTL)
{
   if (_no_child_windows()) {
      _message_box("No buffer is open");
      return;
   }
   if (_isno_name(p_DocumentName) || p_buf_name == '') {
      _message_box("No buffer is open");
      return;
   }
   save();
   //shell('Typora ' p_buf_name, 'QA');
   shell('C:\Program Files\Typora\Typora.exe ' p_buf_name,'QA');
}