Removes the registration of an I/O statistics structure used for maintaining I/O statistics on a particular device.
#include <sys/types.h> #include <sys/errno.h> #include <sys/iostat.h>
void iostdel ( devstatp)
union {
struct ttystat *ttystp;
struct dkstat *dkstp;
} devstatp;
The iostdel kernel service removes the registration of an I/O statistics structure for a device being terminated. The device's ttystat or dkstat structure should have previously been registered using the iostadd kernel service. Following a return from the iostdel service, the iostat command will no longer display statistics for the device being terminated.
In AIX 5.2, support for Multi-Path I/O (MPIO) was added to the iostdel kernel service. For an MPIO device, the anchor is the disk's dkstat structure. An anchor (disk) may have several paths associated with it. Each of these paths can have a dkstat structure registered using the iostadd kernel service. The semantics for unregistering a dkstat structure for an MPIO device are more restrictive than for a non-MPIO device. All paths must unregister before the anchor (disk) is unregistered. If the anchor (disk) dkstat structure is unregistered before all of the paths associated with it are unregistered, the iostdel kernel service will remove the registration of the anchor (disk) dkstat structure and all remaining registered paths.
| devstatp | Points to an I/O statistics structure previously registered using the iostadd kernel service. |
The iostdel kernel service can be called from the process environment only.
The iostdel service has no return values.
The iostat command.
The iostadd kernel service.
Kernel Extension and Device Driver Management Kernel Services in AIX 5L Version 5.2 Kernel Extensions and Device Support Programming Concepts.