Strings in C
Thanks – glad I could be of help.
I don't know what books you are using, but string concatenation was an
extension added by the ANSI committee and wasn't present in K&R. If you're
using older books, it might not be mentioned (or maybe they were just too
lazy to revise the example…)
At the same time as string concatenation, the ANSI committee added "token
pasting" and "stringization" operators to preprocessor macros. They work
like this:
#define FOO(x) abc##x
#define STR(x) #x
The macro invocation
FOO(xyz)
expands to
abcxyz
and the macro invocation
STR(xyz)
expands to "xyz". These are pretty useful in certain specific cases.
–Doug