# edit/replace/subtitute ayat dalam multiple files
$ grep -R --files-with-matches 'MATCH-STRING' . | sort | uniq | xargs perl -pi~ -e 's/MATCHED-STRING/REPLACE-WITH/'

# rename multiple file (extension) 
# more sila sila lah.. $ man rename
$ rename .s/\.ext1/.ext2/. *.ext1

# restart apache tanpa menyusahkan orang ramai 
# atau dimakin hamun hingga menyebabkan anda dibuang kerja
$ /etc/init.d/apache2 graceful