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void *calloc(size_t nmemb£¬size_t size);
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#include<stdlib.h>
struct test
{
int a[10];
char b[20];
}
main()
{
struct test *ptr=calloc(sizeof(struct test),10);
}
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void free(void *ptr);
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main()
{
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#include <sys/mman.h>
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