chktri - check for trigraphs in C source code
chktri [file ...]
This program looks for lines containing trigraphs in C source code. Trigraphs are a way to represent certain characters in C source code as two question marks and a third character. For example, a backslash could be represented as ‘??/’. For a detail specification, see section 188.8.131.52 in the ISO 9899:1990 standard or any decent C book. (You don’t really want to know.)
Lars Wirzenius, firstname.lastname@example.org.