opensolaris man page for dump

dump(9E)							Driver Entry Points							  dump(9E)

NAME
       dump - dump memory to device during system failure

SYNOPSIS
       #include <sys/types.h>
       #include <sys/ddi.h>
       #include <sys/sunddi.h>

       int dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblk);

INTERFACE LEVEL
       Solaris specific (Solaris DDI). This entry point is required. For drivers that do not implement dump() routines, nodev(9F) should be used.

ARGUMENTS
       dev	 Device number.

       addr	 Address for the beginning of the area to be dumped.

       blkno	 Block offset to dump memory.

       nblk	 Number of blocks to dump.

DESCRIPTION
       dump()  is  used  to  dump  a  portion of virtual address space directly to a device in the case of system failure. It can also be used for
       checking the state of the kernel during a checkpoint operation. The memory area to be dumped is specified by addr (base address)  and  nblk
       (length). It is dumped to the device specified by dev starting at offset blkno. Upon completion dump() returns the status of the transfer.

       When  the  system  is panicking, the calls of functions scheduled by timeout(9F) and ddi_trigger_softintr(9F) will never occur. Neither can
       delay(9F) be relied upon, since it is implemented via timeout(). See ddi_in_panic(9F).

       dump() is called at interrupt priority.

RETURN VALUES
       dump() returns 0 on success, or the appropriate error number.

SEE ALSO
       cpr(7), nodev(9F)

       Writing Device Drivers

SunOS 5.11							    9 Oct 2001								  dump(9E)