Stringizing operator in C not working on linux -


i have following code works expected in windows on ubuntu error "tostring1 not declared in scope".

#include <stdio.h> #define                    2 #define b                    3 #define c                    4 #define d                    5 #define tostring1(s)         #s #define tostring(s)          tostring1(s) #define numbers              a,b,c,d #define numberss             tostring(numbers) int main() {  int a1 = 0, a2 = 0, a3 = 0, a4 = 0;  if (sscanf_s(numberss, "%d,%d,%d,%d", &a1, &a2, &a3, &a4) == 4)  {      printf("the numbers assigned correctly");  }  printf("%d %d %d %d ", a1, a2, a3, a4); }

what reason that? if remove tostring1 , make 

#define tostring(s)           #s

the result 0 every variable on both windows , ubuntu.

can have explanation this?

the compiler says:

 error: macro "tostring1" passed 4 arguments, takes 1   sscanf(numberss, "%d,%d,%d,%d",a1,a2,a3,a4);

indeed, numberss tostring(numbers) , numbers is a,b,c,d

so need variable macro magic here work correctly:

#define                    2 #define b                    3 #define c                    4 #define d                    5 #define tostring1(s...)         #s #define tostring(s...)          tostring1(s, __va_args__)  #define numbers              a,b,c,d #define numberss             tostring(numbers)  int main() {     int a1,a2,a3,a4;     sscanf(numberss, "%d,%d,%d,%d",&a1,&a2,&a3,&a4);      printf("%d %d %d %d", a1,a2,a3,a4);  }

online: https://ideone.com/pupd6x

(also, please note have fixed sscanf take addresses)


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