why does strstr return a pointer to a signed char?

The trouble comes with compilers that try to be (too) helpful by warning whenever you have a signed/unsigned mismatch (especially via pointers).

So, if you've carefully defined all your text as 'unsigned', you can get loads of warnings with the string library functions...

:-(

Therefore I have three typedefs in my header:

U8 - for 8-bit things that specifically need to be unsigned;

S8 - for 8-bit things that specifically need to be signed;

TXT - for things that are "text" and, therefore, likely to be used with the string library functions.

The trouble comes with compilers that try to be (too) helpful by warning whenever you have a signed/unsigned mismatch (especially via pointers).

So, if you've carefully defined all your text as 'unsigned', you can get loads of warnings with the string library functions...

:-(

Therefore I have three typedefs in my header:

U8 - for 8-bit things that specifically need to be unsigned;

S8 - for 8-bit things that specifically need to be signed;

TXT - for things that are "text" and, therefore, likely to be used with the string library functions.

TXT - for things that are "text" and, therefore, likely to be used with the string library functions.

Thanks - That's an interesting one.

So, if you've carefully defined all your text as 'unsigned', you can get loads of warnings with the string library functions...

So don't do that, then! :-)

I don't (any more) !

The point is that having just U8 and S8 (or equivalent) is not sufficient - you do also need some kind of "unadorned" char...