table of contents
COPY(9) | Kernel Developer's Manual | COPY(9) |
NAME¶
copy, copyin, copyout, copystr, copyinstr — kernel copy functionsSYNOPSIS¶
#include <sys/types.h>#include <sys/systm.h> int
copyin(const void *uaddr, void *kaddr, size_t len); int
copyout(const void *kaddr, void *uaddr, size_t len); int
copystr(const void *kfaddr, void *kdaddr, size_t len, size_t *done); int
copyinstr(const void *uaddr, void *kaddr, 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.
- 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
(if done is
non-
NULL
). - copyinstr()
- Copies a NUL-terminated string, at most
len bytes long, from user-space address
uaddr to kernel-space address
kaddr. The number of bytes actually copied,
including the terminating NUL, is returned in *done
(if done is
non-
NULL
).
RETURN VALUES¶
The copy functions return 0 on success orEFAULT
if a bad address is encountered. In addition,
the copystr(), and copyinstr() functions
return ENAMETOOLONG
if the string is longer than
len bytes.
SEE ALSO¶
fetch(9), store(9)January 7, 1996 | Debian |