Question

Now, the aim of the program is to take four names through a variable argument list and concatenate them using vsprintf() into a single string called ‘total’. As the program currently is, only the first name appears in string ‘total’. How can I solve this problem please? Thanks 🙂

Answer 1

Signature is int vsprintf(char *str, const char *format, va_list ap);.

The second argument is the usual printf format string… so:

void concat(char *total, ...)
{
   va_list pointer;

   va_start(pointer, total);
   vsprintf(total, "%s %s %s %s", pointer);
   va_end(pointer);
}

This of course only works with exactly 4 strings, but you requested to implement this with vsprintf, which doesn’t work for the generic case.

Note: you’re missing <stdio.h>, and it’s int main().