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The Kernel

The kernel provides the basic functionality of the system. You, the user, don't need to know much about it. It defines the following shell commands.

Command: sysinfo options...

Prints information describing the current state of the system to the shell. Possible flags for the options parameters are:

-irq

Print the currently installed IRQ handlers.

-dma

Print the allocated DMA channels.

-mods

List the currently loaded modules.

-mm

Print the state of the memory management subsystem; the number of free and available pages and the kernel break address.

-ps

List all the `live' tasks and information about them.

Command: cookie

Print the contents of the `cookie jar', when the system is booted this is filled with information about the hardware devices which the system possesses.

Command: date

Display the current date and time.

Command: kill pid

Immediately kills the task (or virtual machine) whose ID is the integer pid. If no task with this ID exists or the task may not be killed an error message is printed.

Command: freeze pid

Suspend the task (or virtual machine) whose process-ID is the integer pid. The task will not be runnable until the thaw command is used to reverse the effect of this command.

Command: thaw pid

Allow the task with ID pid to run again. This undoes the effect of the freeze command.

Command: open module-name

This command attempts to open the module called module-name. This ensures that the module is loaded into memory. If the module can be opened successfully it is immediately closed, otherwise an error message is printed.

Command: expunge module-name

Try to remove the module called module-name from memory. This only works if the module has no outstanding references to it and it actually allows you to expunge it. If it can't be expunged an error message is printed.

Command: sleep time

This command suspends the shell for time seconds.

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