Question

Can I know if sscanf modifies the string passed to it. Or can anybody please point me where I can find the source code for sscanf ?

I downloaded glibc and found the following :

extern int sscanf (__const char *__restrict __s,
               __const char *__restrict __format, ...) __THROW;
extern int sscanf (__const char *__restrict __s,
               __const char *__restrict __format, ...) __THROW;

Answer 1

sscanf never modifies the string you pass to it; you can tell by the const qualifier.

You can find the Glibc source code for sscanf on its Gitweb.