trigraphs in X3J11

[Richard A. O'Keefe]

In article <5424 at ico.ISC.COM>, rcd at ico.ISC.COM (Dick Dunn) writes:
> Wait.  I said that ?? (the trigraph introducer, if you will) is not at all
> rare, and this is easy to confirm.  Occurrences of ?? are important because
> they represent situations where the next character could cause trouble.

I just checked a directory containing 126 utility sources (some of which I
got from the net, some of which I got from a friendly wizard years ago) and
4 of them contained ?? inside strings.  If I've understood the rules, only
two of them would actually break.  Rather alarming:  before I made this
check I was happy about trigraphs:  they won't break _my_ code, I said!