On Tue, 17 Nov 2009 12:25:03 GMT, Pádraig Brady said: > You need to explicitly NUL terminate strncpy(): > http://www.pixelbeat.org/programming/gcc/string_buffers.html Umm. Actually, no. It's *nice* if you explicitly do it. However, it's not strictly *required*. Consider this code: struct a { int b, c; char d[20]; } bzero(a,sizeof(a)); /* voila! a->d[19] is now a \0 */ Perfectly valid and we do it all the time. Your referenced web page comments that using memset() or bzero() is inefficient - I wonder if they actually *tested* the difference between using one memset() or bzero() on a large structure compared to lots and lots of explicit initialization statements (i-cache issues probably most important there). The downside is that there's a greater chance of some programmer refactoring code and bollixing it up. (The astute reader will remember a short thread about this not too long ago.. :) And if you're truly careful and always use the strn- variants of the string functions, it's actually possible to *not* null-terminate the strings. But it results in very brittle code and makes Baby Andrew cry, mostly because when somebody adds a printf() to debug the brittle code, it suddenly becomes even more brittle... :)
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