map <F4> :call TitleDet()<cr>
function AddTitle()
    call append(0,"\#!/usr/bin/env bash")
    call append(1,"# ******************************************************")
    call append(2,"# Author       : 90Zeng")
    call append(3,"# Last modified: ".strftime("%Y-%m-%d %H:%M"))
    call append(
 
4,"# Email        : [email protected]")
    call append(5,"# Filename     : ".expand("%:t"))
    call append(6,"# Description  : ")
    call append(7,"# ******************************************************")
    echohl WarningMsg | echo "Successful in adding copyright." | echohl None
endf
 
function
 
 UpdateTitle()
     normal m'
     execute '/# Last modified/[email protected]:.*[email protected]\=strftime(":\t%Y-%m-%d %H:%M")@'
     normal ''
     normal mk
     execute '/# Filename/[email protected]:.*[email protected]\=":\t".expand("%:t")@'
     execute "noh"
     normal 'k
     echohl WarningMsg | echo
 
 "Successful in updating the copyright." | echohl None
endfunction

function TitleDet()
    let n=1
    while n < 10
        let line = getline(n)
        if line =~ '^\#\s*\S*Last\smodified\S*.*$'
            call UpdateTitle()
            return
        endif
        let n = n + 1
    endwhile
    call AddTitle()
endfunction