test/getcanon.c: exit(3) with 0 or 1, not -1 or symbolic error code.

[nmh] / etc / rcvdistcomps

%(void(localmbox))%(void(width))%(putaddr Resent-From: )
%(lit)%(formataddr{addresses})\
%<(nonnull)%(void(width))%(putaddr Resent-To: )\n%>