strcpy() with copying string from one structure to another [closed] - c

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it seems that this is a duplicate question, but I searched stackoverflow's question about that point and non is like to my problem(I think)
I've two variables of a struct each has its own pointer to char, when I tried to copy from one variable's string to another variable's string, nothing happened, although no errors appear, just warning
implicit declaration of function strcpy
incompatible implicit declaration of built-in function 'strcpy'
I read from some questions on stackoverflow that you'd better to use strdup() function instead of strcpy() but when I did, I had an error
too many arguments to function 'strdup'
I read that there's a problem with strcpy() called "segmentation fault" and I knew it's about memory allocation, I don't totally understand what it's exactly and don't know if it's the problem with my code?
and this is my code
struct p
{
char *name;
struct p *next;
};
struct p *ptrary[10];
int main(void)
{
struct p p,q;
p.name="xyz";
p.next=NULL;
ptrary[0]=&p;
strdup(q.name,p.name);
ptrary[1]=&q;
printf("%s\n",ptrary[1]->name);
return 0;
}
so what is the problem and how I can solve it?

Answer 1

strdup() takes only one argument; it malloc's and returns a new block of heap memory containing the duplicated string. (See https://stackoverflow.com/questions/252782/strdup-what-does-it-do-in-c)
Which probably also points to the problem you were having before -- were you remembering to malloc the space for q to copy p's contents into?

Answer 2

change
strdup(q.name,p.name);
to
q.name = strdup(p.name);
see man page of strdup for further details. The strdup() function returns a pointer to a new string.
full code:
#include <stdio.h>
#include <string.h>
struct p
{
char *name;
struct p *next;
};
struct p *ptrary[10];
int main(void)
{
struct p p,q;
p.name="xyz";
p.next=NULL;
ptrary[0]=&p;
q.name = strdup(p.name);
ptrary[1]=&q;
printf("%s\n",ptrary[1]->name);
return 0;
}