updated for version 7.4.235
Problem:    It is not easy to get the full path of a command.
Solution:   Add the exepath() function.
diff --git a/src/proto/os_win32.pro b/src/proto/os_win32.pro
index a4c590f..c149bc8 100644
--- a/src/proto/os_win32.pro
+++ b/src/proto/os_win32.pro
@@ -26,7 +26,7 @@
 int mch_is_linked __ARGS((char_u *fname));
 int win32_fileinfo __ARGS((char_u *fname, BY_HANDLE_FILE_INFORMATION *info));
 int mch_writable __ARGS((char_u *name));
-int mch_can_exe __ARGS((char_u *name));
+int mch_can_exe __ARGS((char_u *name, char_u **path));
 int mch_nodetype __ARGS((char_u *name));
 vim_acl_T mch_get_acl __ARGS((char_u *fname));
 void mch_set_acl __ARGS((char_u *fname, vim_acl_T acl));