```
function! ReName()
   let old_name = expand("<cword>")
    let new_name = input("new name: ",old_name)
    let cmd = "ref.sh ".expand(old_name).expand(" ").expand(new_name)
   :call system(cmd)
endfunction

```

ref.sh is a bash file, context is

```
#! /bin/bash
find . -name '*.[ch]' | xargs sed -i s/$1/$2/g

```

but now, when i use ReName function in vim, it does not work.