将内存分配给结构内的指针结构

Question

如果我有

这样的结构

typedef struct _people {
 char *name;

 bool *exists;

 struct _people **citizens;
} PEOPLE;

如何分配内存以便人们可以访问人员＆gt; citizen [0] - ＆gt;名称？我试过了

info->citizens = malloc(sizeof(PEOPLE *)*numbPeople);

但是当我尝试访问info-＆gt; citizen-＆gt; name时，我在GDB中收到错误消息：

Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x0000000000000008

Answer 1

（我不喜欢C中的typedefing结构）

让sizeof为你工作。

info->citizens = malloc(numbPeople * sizeof *info->citizens)
if (!info->citizens) { /* could not malloc - do something */ }

int i;
for (i = 0; i < numbPeople; ++i) {
    info->citizens[i] = malloc(sizeof *info->citizens[i]);
    if (!info->citizens[i]) { /* could not malloc - do something */ }
}