Question

I’m programming in C (Linux OS). I need to use rindex for finding last occurence of a char specified as function argument.

char * rindex (const char *string, char c);

It works fine though I get warnings:

conflicting types for built-in function ‘rindex’ [enabled by default]

But if I include a string.h header. It gives error,

conflicting types for ‘rindex’

because there rindex is defined as,

char * rindex (const char *string, int c);

But I need to use it as char and also use the string.h for string operations. Is there any possibility? Kindly guide me.

Answer 1

In 7th Edition UNIX™, there were two functions index() and rindex() that are respectively equivalent to the standard C functions strchr() and strrchr(), give or take const (which didn’t exist when those functions were defined, any more than prototypes existed; there wasn’t even C with Classes back then).

You’re running foul of the backwards-compatible declarations of the function rindex(). The names index() and rindex() are archaic, but you can’t use them blithely in your own code. Choose a different function name.