A-6 APPENDIX A: PACKET FILTER OPCODES, EXAMPLES, AND SYNTAX ERRORS
gt (greater than)
Description:
Pops two values from the stack and performs an unsigned comparison. If the first
is greater than the second, a byte containing the value non-zero is pushed onto
the stack; otherwise, a byte containing 0 is pushed. The size of the operands is
determined by the contents of the stack.
Storage Needed:
1 byte
ge (greater than or equal to)
Description:
Pops two values from the stack and performs an unsigned comparison. If the first
is greater than or equal to the second, a byte containing the value non-zero is
pushed onto the stack; otherwise, a byte containing 0 is pushed. The size of the
operands is determined by the contents of the stack.
Storage Needed:
1 byte
and (bit-wise AND)
Description:
Pops two values from the stack and pushes the bit-wise AND of these values
back onto the stack. The size of the operands and the result are determined by
the contents of the stack.
Storage Needed:
1 byte