Thread: strcpy() with an array of strings

Hi. I have a multidimensional arrays of char's that I'm using to hold strings. The multidimensional array is shared with a forked process. I'm getting a segmentation fault when I try to use strcpy to place a string into one of the rows of the mulitidimensional array. Here's my code.

Code:

#include <string.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <stdlib.h>

int shmid;
int main()
{
	int id, index;
                char **shmaddr = (char **)malloc(7 * sizeof(char *));
                shmaddr[0] = (char *)malloc(7 *  50 * sizeof(char));
                for (index = 0; index < 7; index++)
                {
	                shmaddr[index] = shmaddr[0] + index * 50;
                }
	shmid = shmget(IPC_PRIVATE, 4096, IPC_CREAT|0644);
	shmaddr = shmat(shmid, (void *) 0, 0);
 	fork();
                strcpy(shmaddr[0],"stuff");
                printf("First position of shared memory has contents %s\n", shmaddr[0]);
                if (id != 0){
	shmctl(shmid, IPC_RMID, (struct shmid_ds *) 0);}

	return 0;
}

code tags fixed by Hammer.

Oh... that's the code somebody gave me when I told them I wanted a multidimensional char array that was shared between all processes... why then, does replacing the call to strcpy() with

<code>
shmaddr[0] = "stuff";
</code>

work?

Sorry about starting a new thread for the same thing. I won't do that again, but I still could use a hand with this problem. I was allocating the memory wrong before, as you guys pionted out. I fixed that, and now use the following code:

Code:

char ** buf;
int shmid;

shmid = shmget(IPC_PRIVATE, 350 * sizeof(char), IPC_CREAT|0644);
buf = shmat(shmid, (void *) 0, 0);
for (index = 0; index < 7; index++)
{
     buf[index] = buf[0] + index * sizeof(char);
}

But I still can't figure out how to copy a char * array into this space.
Thanks.