command convert: used to convert between styles http://blog.csdn.net/huntinux/article/details/8531178 http://blog.csdn.net/fdipzone/article/details/39651709
command display: used to display a photo
command find http://blog.csdn.net/wenchao126/article/details/8071526 find . -name "*.jpg" -exec display {} ;
4)将find出来的东西拷到另一个地方 copy files that FIND command find to some place else.
find *.c -exec cp '{}' /tmp ';' why? what does '{}' /tmp ';' mean here!