Asm expression misunderstanding with times

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Hello,

Somebody can explain me these lines ?

C++

buffer: db 'hello, world'
times 64-$+buffer db '_'

result : "hello, world____________________________________________________"

I understand these lines below, it makes sense (addresse where we stand minus addresse of the beginning of the program = size of the program in bytes) :

C++

times 510 - ($-$$) db 0

But in the first expression how $+buffer can make 52 ?? i just don't get it why a + not a - ?

Thanks for help by advance :)

What I have tried:

i have tried to fine some explanation on google or whatever but without any success

Posted 3-Aug-16 23:11pm

deck_bsd

Updated 3-Aug-16 23:46pm

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Richard MacCutchan · Accepted Answer · 2016-08-03T23:46:00

C++

buffer: db 'hello, world'
times 64-$+buffer db '_'

Assume the location of buffer is 1000, then the location of times (identified by the $ sign) is 1012.
So:

64 - 1012 = -948
-948 + 1000 = 52

The expression effectively calculates the number of dashes to add to the previous string to make a total of 64 characters.