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From: Giovanni Dicanio on 8 Jan 2009 10:42 Tom Serface wrote: > I was looking at the documentation. I apologize. I didn't think I had > to read into the code to get the actual scoop and from that prototype I > agree totally that it looks like it's asking for number of characters. > In the doco it said "size of the buffer" and didn't even list a wide > version at all. Tom: you don't have to apologize! The documentation writers should! :) One is supposed to read the documentation and trust it, instead of studying the header files (like I've done). G
From: Tom Serface on 8 Jan 2009 11:05 Yeah, but I should know better. I've been around the coffee cup enough times to know where the handle is :o) Tom "Giovanni Dicanio" <giovanniDOTdicanio(a)REMOVEMEgmail.com> wrote in message news:uS1HVfacJHA.1760(a)TK2MSFTNGP05.phx.gbl... > > Tom: you don't have to apologize! The documentation writers should! > :) > > One is supposed to read the documentation and trust it, instead of > studying the header files (like I've done). > > G > > >
From: Giovanni Dicanio on 8 Jan 2009 11:08 Tom Serface wrote: > I've been around the coffee cup enough > times to know where the handle is :o) :D The second time you write that! G
From: Giovanni Dicanio on 8 Jan 2009 11:20 Giovanni Dicanio wrote: > So, the code logic is simpler and there is no need for the loop: > > TCHAR szBuf[ 64*1024 ]; // 64K TCHAR buffer > WORD cchBufMax = _countof(szBuf) - 1; BTW: A small side note... I think that it should be fine to allocate this size (64KB on ANSI builds, or 2*64KB = 128KB on Unicode builds) on the stack (I think that C++ stack is big enough...). However, as an alternative, that memory could be allocated on the heap as well, using convenient std::vector: std::vector< TCHAR > szBuf( 64*1024 ); and TCHAR * pszBuf = &szBuf[0]; Giovanni
From: Mihai N. on 8 Jan 2009 22:34
> I think that Tom was mislead by this documentation (if I read 'cb' > prefix, I think of sizeof(), too, like Tom did; instead, if I read 'cch' > prefix, I think about _countof()). See, the safest way to not be mislead by the documentation is to not read it at all (like me :-) Thing is, in general strings taking a buffer of "characters" (char/TCHAR/wchar_t/WCHAR/whatever) also take a "character count", and the buffer size is in characters. The only exception that I know is the "safe strings" API that has a set of APIs using byte counts (StringCbWhatever). Weird, it feels upside-down. -- Mihai Nita [Microsoft MVP, Visual C++] http://www.mihai-nita.net ------------------------------------------ Replace _year_ with _ to get the real email |