I/O Management

The ChorusOS operating system provides the following I/O management services:

BPF

The BPF feature provides a raw interface to data link layers in a protocol independent fashion. All packets on the network, even those destined for other hosts, are accessible through this mechanism. It must be configured when using the ADMIN_RARP feature, or Dynamic Host Configuration Protocol client (dhclient(1M)).

For more details, see BPF(5FEA).

FS_MAPPER

The FS_MAPPER feature provides support for swap in the IOM. It requires either the IDE_DISK or SCSI_DISK to be configured, as well as VIRTUAL_ADDRESS_SPACE and ON_DEMAND_PAGING.

For more details, see FS_MAPPER(5FEA).

IDE_DISK

The IDE_DISK feature provides an interface to access IDE disks. These disks may then be initialized and used as regular file systems. The IDE_DISK feature relies on the IDE bus support provided by the BSP to get access to disks connected on that bus.

For more details, see IDE_DISK(5FEA).

DEV_MEM

The DEV_MEM feature provides a raw interface to memory devices such as /dev/zero, /dev/null, /dev/kmem and /dev/mem.

For more details, see DEV_MEM(5FEA) .

RAM_DISK

The RAM_DISK feature provides an interface to chunks of memory which can be seen and handled as disks. These disks may then be initialized and used as regular file systems, although their contents will be lost at system shutdown time. This feature is also required to get access to the MS-DOS file system which is usually embedded as part of the system boot image.

For more details, see RAM_DISK(5FEA).

FLASH

The FLASH feature provides an interface to access a memory device. The flash memory may then be formatted, labelled and used to support regular file systems. The FLASH feature relies on the flash support based on the Flite 1.2 BSP, and is not supported for all target family architectures. See the appropriate book in the ChorusOS 4.0 Target Family Documentation Collection for details of which target family architecture supports the Flite 1.2 BSP.

For more details, see FLASH(5FEA).

VTTY

The VTTY feature provides support for serial lines on top of the BSP driver for higher levels of protocols. It is used by the SLIP and PPP features.

For more details, see VTTY(5FEA).

SCSI_DISK

The SCSI_DISK feature provides an interface to access SCSI disks. The SCSI_DISK feature relies on the SCSI bus support provided by the BSP to access disks connected on that bus.

For more details, see SCSI_DISK(5FEA).

IOM_IPC

The IOM_IPC feature provides support for the ethIpcStackAttach(2K) system call and the corresponding built-in C_INIT(1M) command, ethIpcStackAttach. If the feature is not configured, the ethIpcStackAttach(2K) system call of the built-in C_INIT command will display an error message.

If the IOM_IPC feature is set to true, an IPC stack is included in the IOM system actor. The IPC stack may be attached to an Ethernet interface.

For more details, see IOM_IPC(5FEA).

IOM_OSI

The IOM_OSI feature provides support for the ethOSIStackAttach(2K) system call.

If the IOM_OSI feature is set to true, an OSI stack is included in the IOM system actor. The OSI stack may be attached to an Ethernet interface.

For more details, see IOM_OSI(5FEA).