__copy_to_user(9) [suse man page]

__COPY_TO_USER(9)					    Memory Management in Linux						 __COPY_TO_USER(9)

NAME

       __copy_to_user - Copy a block of data into user space, with less checking.

SYNOPSIS

       unsigned long __must_check __copy_to_user(void __user * to, const void * from, unsigned long n);

ARGUMENTS

       to
	   Destination address, in user space.

       from
	   Source address, in kernel space.

       n
	   Number of bytes to copy.

CONTEXT

       User context only. This function may sleep.

DESCRIPTION

       Copy data from kernel space to user space. Caller must check the specified block with access_ok before calling this function.

       Returns number of bytes that could not be copied. On success, this will be zero.

COPYRIGHT

Kernel Hackers Manual 2.6.					     July 2010							 __COPY_TO_USER(9)

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

NAME

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

SYNOPSIS

     #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 num-
		   ber 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 or EFAULT 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)

BSD
								  January 7, 1996							       BSD