I'm too tired to dig for the exact words in the ISO standard, but I had the impression that the official C rule these days is that the effect of writing on a string literal is undefined. So it's legal for an implementation to make strings read-only, or to point several references to "What's the recipe today, Jim" to one copy of the stripng in memory, and even to point uses of "Jim" to the tail of the same string. Or both. It is also legal for every string literal to reside in its own memory and to be writable, but since the effect is undefined, code that relies on that is on thin ice, especially if meant to be portable code. I have used, and even fixed (unrelated) bugs in, a compiler that merged identical strings. I forget whether it also looked for suffix matches. Whether the strings went in read-only memory was up to the code generator (of course); in the new back-end I wrote for it, I made them so. This turned up quite a few fumbles in very-old UNIX code that assumed unique, writable string literals, especially those that called mktemp(3). To my mind that just meant the programs needed to be fixed to match current standards (just as many old programs needed fixes to compile without error in ISO C), so I fixed them. I didn't (and still don't) like Joy's heavy-handed hack, but I see his point, and think it's just fine for the language rules to allow the compiler to do it hacklessly. Norman Wilson Toronto ON