RD(1)

NAME
rd, rm- Register manipulation commands

SYNOPSIS
rd [c|d|u]

rm register-name new-contents

DESCRIPTION
The rd command is used to display the contents of processor registers. Without any arguments, the rd command displays the contents of the general register set at the point at which the kernel debugger was entered. With the 'c' argument, the processor control registers %cr0, %cr1, %cr2 and %cr4 are displayed, while with the 'd' argument the processor debug registers are displayed. If the 'u' argument is supplied, the registers for the current task as of the last time the current task entered the kernel are displayed.

The rm command allows modification of a register. The following register names are valid: %eax, %ebx, %ecx, %edx, %esi, %edi, %esp, %eip, and %ebp. Note that if two '%' symbols are used consecutively, the register set displayed by the 'u' argument to the rd command is modified.

LIMITATIONS
Currently the 'rm' command will not allow modification of the control or debug registers.

Currently neither the 'rd' command nor the 'rm' command will display or modify the model specific registers on the Pentium and Pentium Pro families.

ENVIRONMENT
None.

SMP CONSIDERATIONS
None.

EXAMPLES

rd  Display general register set.

rm %eax 0
    Set the contents of %eax to zero. This will be the value of %eax when kdb returns from the condition which invoked it.

rm %%eax 0
    Set the value of the %eax register to zero. This will be the value the user-mode application will see upon returning from the kernel.