Unicode again
in [Win32 API]
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From: Jean on 25 Apr 2010 10:32 Hello this code works: unsigned char buffer[1025]; fopen("toto.bmp", "rb"); fread(buffer, sizeof(unsigned char),1024, pf); fclose(pf); if(buffer[0] == 'B' && buffer[1] == 'M') ... this code does not work: (compiled with UNICODE and _UNICODE) WCHAR buffer[1025]; _wfopen(L"toto.bmp", L"rb"); fread(buffer,sizeof(WCHAR),1024,pf); fclose(pf); if(buffer[0] == 'B' && buffer[1] == 'M') ... it's the comparison that does not work. (i tried if(buffer[0] == L'B' && buffer[1] == L'M') too) any idea ? jean
From: Xavier Roche on 25 Apr 2010 10:46 Jean a écrit : > this code does not work: (compiled with UNICODE and _UNICODE) You are incorrectly assuming that fread() is unicode-aware. But it's not: fread() reads _bytes_, not characters, and your example will not work unless the file is UCS-2 (little endian) encoded. The only impact of unicode is on the (w)fopen side: once the file is opened, fread will behave strictly identically. By the way, defining UNICODE is not necessary in your case, as you are using explicit UCS2 functions such as _wfopen ; UNICODE would have an impact on _tfopen and friends only. [ And AFAICS, you are processing a binary BMP file - you should stick to unsigned char buffers ]
From: ScottMcP [MVP] on 25 Apr 2010 11:56 This is comparing unicode data with ANSI characters: if(buffer[0] == 'B' && buffer[1] == 'M') Try it this way: if(buffer[0] == L'B' && buffer[1] == L'M')
From: Angus on 25 Apr 2010 16:54 On 25 Apr, 16:56, "ScottMcP [MVP]" <scott...(a)mvps.org> wrote: > This is comparing unicode data with ANSI characters: > > if(buffer[0] == 'B' && buffer[1] == 'M') > > Try it this way: > > if(buffer[0] == L'B' && buffer[1] == L'M') Or if you use C++ you could use the wfstream.
From: Jean on 26 Apr 2010 00:46
>And AFAICS, you are processing a binary BMP file - you should stick to >unsigned char buffers it was an example, my program works with any file type Jean "Xavier Roche" <xroche(a)free.fr.NOSPAM.invalid> a �crit dans le message de news: hr1kjn$14m$1(a)news.httrack.net... > Jean a �crit : >> this code does not work: (compiled with UNICODE and _UNICODE) > > You are incorrectly assuming that fread() is unicode-aware. But it's not: > fread() reads _bytes_, not characters, and your example will not work > unless the file is UCS-2 (little endian) encoded. > > The only impact of unicode is on the (w)fopen side: once the file is > opened, fread will behave strictly identically. > > By the way, defining UNICODE is not necessary in your case, as you are > using explicit UCS2 functions such as _wfopen ; UNICODE would have an > impact on _tfopen and friends only. > > [ And AFAICS, you are processing a binary BMP file - you should stick to > unsigned char buffers ] |