mojave man page for copyin

COPY(9) 						   BSD Kernel Developer's Manual						   COPY(9)

NAME
     copy, copyin, copyinstr, copyout, copystr -- kernel copy functions

SYNOPSIS
     #include <sys/types.h>
     #include <sys/systm.h>

     int
     copyin(const void *uaddr, void *kaddr, size_t len);

     int
     copyinstr(const void *uaddr, void *kaddr, size_t len, size_t *done);

     int
     copyout(const void *kaddr, void *uaddr, size_t len);

     int
     copystr(const void *kfaddr, void *kdaddr, size_t len, size_t *done);

DESCRIPTION
     The copy functions are designed to copy contiguous data from one address to another.  All but copystr() copy data from user-space to kernel-
     space or vice-versa.

     The copy routines provide the following functionality:

     copyin()	   Copies len bytes of data from the user-space address uaddr to the kernel-space address kaddr.

     copyinstr()   Copies a NUL-terminated string, at most len bytes long, from user-space address uaddr to kernel-space address kaddr.  The num-
		   ber of bytes actually copied, including the terminating NUL, is returned in *done.

     copyout()	   Copies len bytes of data from the kernel-space address kaddr to the user-space address uaddr.

     copystr()	   Copies a NUL-terminated string, at most len bytes long, from kernel-space address kfaddr to kernel-space address kdaddr.  The
		   number of bytes actually copied, including the terminating NUL, is returned in *done.

RETURN VALUES
     The copy functions return 0 on success or the following error on failure:

     [EFAULT]		If a bad address is encountered. When this error is returned, the contents of the destination buffer ( *kaddr for
			copyin(), copyinstr(), and copystr(); *uaddr for copyout()) are undefined. For copyinstr() and copystr(), the contents of
			the *done parameter are also undefined on a return of EFAULT.

     In addition to EFAULT, copystr() and copyinstr() on failure will return:

     [ENAMETOLONG]	When the string is longer than len bytes. On this error return, the destination buffer is not null-terminated, but the
			*done parameter is maintained.

SEE ALSO
     fetch(9), store(9)

BSD
								  October 2, 2008							       BSD