how do I configure vim to set the executable bit on scripts?

I am trying to configure vim so that when I write a new script it will automatically set the executable bit on it when I write to it for the first time without the annoying Code: W16: Warning: Mode of file "b.sh" has changed since editing started See ":help W16" for more info. [O]K, (L)oad File: No matter what I do though, it doesn't seem to work. here is my .vimrc: Code: so ~/.vim/mod.vim autocmd BufNewFile * let fname=expand("%:p") autocmd BufNewFile *.pl execute "autocmd BufWritePost ".fname." call SetExecutableBit()" autocmd BufNewFile *.sh execute "autocmd BufWritePost ".fname." call SetExecutableBit()" autocmd BufNewFile *.rb execute "autocmd BufWritePost ".fname." call SetExecutableBit()" autocmd BufNewFile *.py execute "autocmd BufWritePost ".fname." call SetExecutableBit()" and this is my .vim/mod.vim file: Code: function! SetExecutableBit()         let fname=expand("%:p")         execute "autocmd FileChangedShell ".fname         execute "!chmod a+x ".fname         execute "autocmd! FileChangedShell ".fname endfunction

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