🚀 go-pugleaf

 >Actually, one never NEEDS trigraphs; they're required to be 
 >supported as a convenience when interchanging source code among sites or 
 >equipment with poor support for the C source character set.

There are character sets, which do not support all C language characters, such 
as braces and brackets (example: 7-bit german). While it is usually possible to

use the characters corresponding to these ASCII codes instead (...but almost 
unreadable), it is likewise possible that some text file exchange program 
silently converts these special characters into PC, ISO or ECMA 8-bit 
equivalents. Trigraph characters are available in all roman-style character sets

and will be understood by all machines.

While I never saw a machine-readable program actually using these trigraphs, I 
saw printed demo programs in german books or student lessons, where the braces, 

brackets, backslashes etc. were added by pencil, because german typewriters 
usually do not support them. 

While trigraphs in a C program are likewise unreadable as the german umlauts, 
they can be hidden by macros without accidentally undergoing invalidating 
conversions.

                Gru!!s, Andreas

 
 
 

 * Origin: kaiser@ananke.stgt.sub.org - Stuttgart FRG (2:244/7014)