man Pages(9E): DDI and DKI Driver Entry Points
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NAME

write - write data to a device

SYNOPSIS

#include <sys/types.h>
#include <sys/errno.h>
#include <sys/open.h>
#include <sys/cred.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>

int prefixwrite(dev_t dev, struct uio * uio_p, cred_t * cred_p);

INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI). This entry point is optional.

ARGUMENTS

dev
Device number.
uio_p
Pointer to the uio (9S)structure that describes where the data is to be stored in user space.
cred_p
Pointer to the user credential structure for the I/O transaction.

DESCRIPTION

Used for character or raw data I/O, the driver write( ) routine is called indirectly through cb_ops(9S) by the write(2) system call. The write( ) routine supervises the data transfer from user space to a device described by the uio (9S)structure.
The write routine should check the validity of the minor number component of dev and the user credentials pointed to by cred_p (if pertinent).

RETURN VALUES

The write( ) routine should return 0 for success, or the appropriate error number.

SEE ALSO

read (2),read (9E),cb_ops(9S), uio (9S)
Writing Device Drivers