3 ms·true. it appeared in 1985 http://man.cat-v.org/unix_8th/7/ http://man.cat-v.org/unix_8th/7/by gcb0 13y agotrue. it appeared in 1985 http://man.cat-v.org/unix_8th/7/ http://man.cat-v.org/unix_8th/7/