The &
has a special meaning in the shell. Escape it with \
or put the url in quotes to avoid this problem.
wget http://search.yahoo.com/404handler?src=search\&p=food+delicious -O test.html
or
wget "http://search.yahoo.com/404handler?src=search&p=food+delicious" -O test.html
In many Unix shells, putting an &
after a command causes it to be executed in the background.