Question

How to copy existing struct to new allocated struct in C

Answer 1

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

enum { buffer_size = 32 };

struct buffer {
    size_t id;
    char bufferX[buffer_size];
};

int main(void) {
    struct buffer buf;
    
    buf.id = 5893;
    strcpy(buf.bufferX, "c programming");
    printf("buf.id: %d : buf.bufferX: %s\n", buf.id, buf.bufferX);

    struct buffer *p = (struct buffer *)malloc(sizeof(struct buffer));
 
    if (p == NULL) {
        puts("Malloc error");
        exit(1);
    }
 
    memcpy(p, &buf, sizeof(struct buffer));
    
    printf("p->id: %d : p->bufferX: %s", p->id, p->bufferX);
    
    free(p);
}





/*
compile:

buf.id: 5893 : buf.bufferX: c programming
p->id: 5893 : p->bufferX: c programming

*/

 

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