Thread: Copy operation error I do not understand

This is the error I was given

Code:

error: array subscript is not an integer
     *end = num->buff[pos];

end & num->buff are both pointers to an unsigned char, num->buff obviously is an array of unsigned char but nevertheless is still a pointer to an unsigned char, I was under the impression that the above code would copy the value of num->buff[pos] into the unsigned char pointed to by *end, can anybody enlighten me as to what the possible problem is?

Incedently this is a hobby project so there should be no moral/ethical issues here.

What is the type of pos? Maybe the issue lies there.

Please post the code if possible in code tags so we can see it in context.

Here's a copy paste of relevant areas of code.

Code:

#define ZIC signed char
#define ZUC unsigned char
#define ZIS signed short
#define ZUS unsigned short
#define ZI signed int
#define ZU unsigned int
#define ZIL signed long
#define ZUL unsigned long

typedef bool zb_t;
typedef ZIC zic_t;
typedef ZUC zuc_t;
typedef ZIS zis_t;
typedef ZUS zus_t;
typedef ZI zi_t;
typedef ZU zu_t;
typedef ZIL zil_t;
typedef ZUL zul_t;
// ...
typedef struct ZUV {
    zus_t size;
    zul_t bits;
    char const *endian;
    zuc_t *buff;
} zuv_t;
// ...
void _zuvMax( zuv_t *num, zuc_t *max, zuc_t *end, zus_t *pos ) {
    zul_t bits = num->bits % CHAR_BIT;
    *pos = num->size - 1;
    *end = num->buff[pos];
    *max = ~(UCHAR_MAX << bits);
}

never mind just realised my error, forgot to dereference pos