On Thu, Apr 30, 2009 at 01:38:22PM +0200, Abdelrazak Younes wrote:
> From what I read CreateFile (just like most other functions that take a
> string param) is
> nothing more than a macro that during precompilation expands to CreateFileA
> or CreateFileW depending on the definition of UNICODE (when UNICODE is
> defined it will expand to CreateFileW).
I have verified that this is also the case with mingw. Given that we
don't define UNICODE, we are actually using the A version (but see below).
> Hum, the problem is AFAIU that CreateFileA takes a 'char *' and
> CreateFileW takes a 'wchar_t *' so I fear that we'll get a compilation
> error on MSVC but I cannot test right now. I came across similar problem
> recently while trying to dlopen a library by name...
This is what I get when compiling the attached C program with UNICODE
either defined or not:
$ touch zzz
$ gcc -mno-cygwin getfileinfo.c -o getfileinfo
$ ./getfileinfo.exe zzz
Volume: 1681330194
Index: 54473
$ gcc -mno-cygwin -DUNICODE getfileinfo.c -o getfileinfo
getfileinfo.c: In function `main':
getfileinfo.c:14: warning: passing arg 1 of `CreateFileW' from incompatible
pointer type
$ ./getfileinfo.exe zzz
Cannot access "zzz"
So, I think that it will be very clear if and when there will be problems.
Moreover, note that toFileSystemEncoding() uses QFile::encodeName(), and
this is what the Qt docs state about it:
By default, this function converts \a fileName to the local 8-bit
encoding determined by the user's locale. This is sufficient for
file names that the user chooses. File names hard-coded into the
application should only use 7-bit ASCII filename characters.
Thus, we are doing the right thing, me thinks.
--
Enrico
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
int main(int argc, char **argv)
{
if (argc != 2) {
printf("Usage: %s <filename>\n", argv[0]);
exit(0);
}
// Open the file
HANDLE h = CreateFile(argv[1], 0,
FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL);
if (h == INVALID_HANDLE_VALUE) {
printf("Cannot access \"%s\"\n", argv[1]);
exit(1);
}
// Get information
BY_HANDLE_FILE_INFORMATION info;
if (GetFileInformationByHandle(h, &info) == 0) {
printf("Cannot get info for \"%s\"\n", argv[1]);
exit(1);
}
CloseHandle(h);
// Get the serial number of the volume containing the file.
ULONG st_dev = info.dwVolumeSerialNumber;
// Get the unique identifier associated to the file on the volume.
ULONGLONG highbits = info.nFileIndexHigh & 0x0000FFFF;
ULONGLONG st_ino = (highbits << sizeof(ULONG)) | info.nFileIndexLow;
printf("Volume: %u\n", st_dev);
printf("Index: %I64i\n", st_ino);
return 0;
}
