10-15-2010
If user space heap and kernel space heaps are diff, can the allocated kernel/ user areas be accessed by mapping in either case all times?
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LEARN ABOUT OSF1
copyinstr
copyinstr(9r) copyinstr(9r)
NAME
copyinstr - General: Copies a null-terminated string from a user address space to a kernel address space
SYNOPSIS
int copyinstr(
char *user_src,
char *kernel_dest,
int maxlength,
int *lencopied );
ARGUMENTS
Specifies the address in user space of the null-terminated string to be copied. Specifies the address in kernel space to copy the null-
terminated string to. Specifies the maximum number of bytes to copy. Specifies the actual length of the string copied.
DESCRIPTION
The copyinstr routine copies a specified null-terminated string from the unprotected user address space to a specified address in the pro-
tected kernel address space.
CAUTIONS
If the string being copied is not null terminated, copyinstr copies maxlength bytes into the kernel address space.
RETURN VALUES
Upon successful completion, copyinstr returns the value 0 (zero) and the actual length of the string copied to the lencopied argument. Oth-
erwise, it returns one of the following error constants defined in /usr/sys/include/sys/errno.h: The address in user space that you speci-
fied in the user_src argument cannot be accessed. The length of the string exceeds the maxlength value.
SEE ALSO
Routines: copyoutstr(9r)
copyinstr(9r)