KernelDebugRef - Unary Operators

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Kernel Debugger Reference

Introduction Installing the Kernel Debugger The T Terminal Emulator Entering the Debugger Expressions Operator Precedence Binary Operators Unary Operators Numbers Strings Symbol Files Using Kernel Debugger Commands The Breakpoint (BP) Command Breakpoint Commands External Commands Using Default Commands External Debugger Commands Setting Useful Breakpoints Debugging Kernel Device Drivers Debugging VM Start Sessions Debugging a Remote System Notices

The following operators expect a single argument.

Ranges are an address and either a length or an end. 4544:0 L5 is address (4544:0) and a length of 5 objects. If you are dumping words, 5 words are dumped. #8:32 50 is a range of bytes from address 8:32 to and including 8:50.

Note: For <ranges>, if the second address has a unary operator such as . or #, then it must be separated by a comma from the first. Parentheses work as well, for example:

• db ds:40,%40000 Correct
• db ds:40 (%40000) Correct
• db ds:40 %40000 Incorrect

These results are caused by the way in which the expression evaluator parses the input.

• | Task number/address operator
• . Address type is segment:offset
• # Address type is selector:offset
• % Address type is linear
• %% Address type is physical
• - Two's complement
• ! Logical NOT operator
• NOT Bitwise one's complement
• SEG Returns the segment portion
• OFF Returns the offset portion
• BY 1-byte value from the address
• WO 2-byte value from the address
• DW 4-byte value from the address
• POI 4-byte address from the address
• PORT 1-byte value from an 8-bit I/O port
• WPORT 2-byte value from a 16-bit I/O port