2 Questions

 BBS: Inland Empire Archive
Date: 02-14-93 (17:43)             Number: 163
From: DAVIDSON CORRY               Refer#: NONE
  To: MIKE KOST                     Recvd: NO  
Subj: 2 Questions                    Conf: (1) 80xxx

MK: What is the $ for? i've seen it used, and since i've learned by example :, without a good beginning tutor book, i never found out. In many assemblers (particularly 80x86 assemblers, especially those whose syntax derives from the Intel/MASM antecedents) the built-in symbol $ represents the current location counter. That is, in JMP $+3 the $ represents the offset of the JMP opcode. In MASM-compatible assemblers, a symbol has not only offset information associated with it, but also type information. $ is equivalent to THIS LABEL. THIS is a keyword meaning "at the current offset within the current segment", and it takes a type argument: BYTE, WORD, DWORD... for data types, or LABEL for code targets. For simplicity's sake, many of us read $ as the word "here". Thus we'd pronounce JMP $+3 as "jump here plus three" -- JMP to the location three bytes beyond the offset of the JMP opcode. --- Maximus 2.01wb * Origin: Cornerstone C,C++,Assy,Windows (206)362-4283 (1:343/22)
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