Re: Message buffer and printf reentrancy patch

From: Daniel C. Sobral (dcs_at_tcoip.com.br)
Date: 06/24/03

  • Next message: Pawel Jakub Dawidek: "Jailed sysvipc implementation." 
    Date: Tue, 24 Jun 2003 08:51:31 -0300
To: Erik Trulsson <ertr1013@student.uu.se>

    Erik Trulsson wrote:
    >
    > With a C99 compiler it is always true. In C89 it was implementation
    > defined if integer division rounded towards zero or towards
    > negative-infinity. In C99 integer division always rounds towards zero.
    > This combined with the fact that (a/b)*b + a%b == a is always true (for
    > integer a,b and b!=0) means that (neg_int % pos_int <= 0 ) is always
    > true in C99, while it wasn't always true in C89.

    Heh. I recall when ANS Forth was being discussed that people found it
    silly all the discussion around whether signed integer division was
    symmetric or floored, when even C didn't bother with it. :-)

    (And, if you are interested in such things, the problem was that
    Forth-79 was symmetric, Forth-83 was floored (or vice versa -- I don't
    know); the solution was to leave / as implementation defined and
    creating two new operators: one symmetric and one floored. :) 

    -- 
Daniel C. Sobral                   (8-DCS)
Gerencia de Operacoes
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VIVO Centro Oeste Norte
Fones: 55-61-313-7654/Cel: 55-61-9618-0904
E-mail: Daniel.Capo@tco.net.br
         Daniel.Sobral@tcoip.com.br
         dcs@tcoip.com.br
Outros:
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	capo@notorious.bsdconspiracy.net
I finally got it all together ...
but I forgot where I put it.
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