q Files

Q may be run in a pipe (in conjunction with using the -i option to tell it what do do). Standard input must a pipe or redirected from other than a tty. Q buffers the entire file (i.e. it waits for end of file on its input before processing). So, avoid using with tail -f (unless you plan to explicitly kill tail) Examples

$ echo aaa|q -i "y a b^J"
bbb

$ echo aaa >t5; q -i "y a z^J" < t5 > t6;cat t6; rm t5 t6
zzz