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clinuxstructxdr

Use a struct in a header file [ C - Linux ]

I tried to use an external struct but when I compile my c code I obtained this message:

subscripted value is neither array nor pointer nor vector.

Why?

messaggio.h

struct Request {
    struct {
        u_int data_len;
        float *data_val;
    } data;
    bool_t last;
};
typedef struct Request Request;

main.c 

#include "messaggio.h"

int main(void){
 struct Request x;
 x.data[0] = 4.6;
 printf("%f\n",x.data[0]);
 return 0;
}
Solution

  • The x.data is a struct, so you cannot use [] with it. Maybe you want x.data.data_val[0].

    Try this code:

    struct Request x;
x.data.data_len = 5; // initialize the length, use any value you need
x.data.data_val = (float *) malloc(x.data.data_len * sizeof(float));
x.data.data_val[0] = 4.6