Interactive selection to the traditional pipe concept on UNIX
Description
percol is an interactive grep tool in your terminal. percol
receives input lines from stdin or a file,
lists up the input lines,
waits for your input that filter/select the line(s),
and finally outputs the selected line(s) to stdout.
Since percol just filters the input and output the result to stdout, it can be
used in command-chains with | in your shell (UNIX philosophy!).
