How to grep and execute a command (for every match)

Question

How to grep in one file and execute for every match a command?

File:

foo
bar
42
foo
bar

I want to execute to execute for example

Answer 1

What you really need is a xargs command. http://en.wikipedia.org/wiki/Xargs

grep file foo | xargs date %s.%N

example of matching some files and converting matches to the full windows path in Cygwin environment

$ find $(pwd) -type f -exec ls -1 {} \; | grep '\(_en\|_es\|_zh\)\.\(path\)$' | xargs cygpath -w