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ruct void
原标题:C struct to void* pointer

我有以下定义:

typedef struct {
   int type;
   void* info;
} Data;

之后,我还有其他几个方面,即想利用以下职能将空白* 分配给:

Data* insert_data(int t, void* s)
{
    Data * d = (Data*)malloc(sizeof(Data));
    d->type = t;
    d->info = s;

    return d;
}

struct {
   ...
} Struct#;

那时,我只是呼吁

insert_data(1, variable_of_type_Struct#);

一俟汇编,就会发出警告。

warning: assignment from incompatible pointer type

i 试图将“变数”插入到(避免*)但 did

insert_data(1, (void *) variable_of_type_Struct#);

如何消除这一警告?

成就

最佳回答

在“结构”的地址中通过,而不是其复制件(即不通过价值):

insert_data(1, &variable_of_type_Struct);
问题回答

穿孔物体:

struct your_struct_type bla;

insert_data(1, &bla);

希望这一方案有助于!

#include <stdio.h>
#include <stdlib.h>

typedef struct {
   int type;
   void* info;
} Data;

typedef struct {
    int i;
    char a;
    float f;
    double d;  
}info;

Data* insert_data(int t, void* s)
{
    Data * d = (Data*)malloc(sizeof(Data));
    d->type = t;
    d->info = s;

    return d;
}

int main()
{
    info in; 
    Data * d;
    d = insert_data(10, &in);

    return 0;
}

我不清楚的是:

struct {
   ...
} Struct#;

因此,我在将“结构”的地址插入“insert_data(1, &variable_of_type_Struct);之后,对你的方案进行了细微的清理,没有警告。

#include <stdlib.h>
#include <stdio.h>

typedef struct {
    int type;
    void* info;
} Data;

Data* insert_data(int t, void* s);

Data variable_of_type_Struct;

Data* insert_data(int t, void* s)
{
    Data * d = (Data*)malloc(sizeof(Data));
    d->type = t;
    d->info = s;

    return d;
}

void test()
{
    insert_data(1, &variable_of_type_Struct);
}

insert_data waits for a void*, you put a Data.

insert_data(1, &variable_of_type_Struct#);

它是间接的。





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