wc

POSIX 7

Does word, line, character and other similar counts.

Mnemonic: Word Count.

[ "$(printf 'a\nb c\n'| wc)" = "      2       3       6" ] || exit 1

Meaning of output:

2: newline count
3: word count
6: byte count

Options:

c: bytes only
m: chars only
l: newlines only
L: max line length only
w: words only

To omit the filename: use stdin! http://stackoverflow.com/questions/3746947/get-just-the-integer-from-wc-in-bash

wc <file