Q> Как создать hard link на NTFS?
A>

#include <windows.h>
#include <stdio.h>
#pragma hdrstop
#define err doerr( __FILE__, __LINE__ )

void doerr( const char *file, int line )
{
DWORD e;

e = GetLastError();
if ( e == 0 )
return;

printf( "%s(%d): gle = %lu\n", file, line, e );
exit( 2 );
}

void enableprivs()
{
HANDLE hToken;
byte buf[sizeof TOKEN_PRIVILEGES * 2];
TOKEN_PRIVILEGES & tkp = *( (TOKEN_PRIVILEGES *) buf );

if ( ! OpenProcessToken( GetCurrentProcess(),
TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken ) )
err;

// берем SeBackupPrivilege и SeRestorePrivilege

if ( !LookupPrivilegeValue( NULL, SE_BACKUP_NAME, &tkp.Privileges[0].Luid ) )
err;

if ( !LookupPrivilegeValue( NULL, SE_RESTORE_NAME, &tkp.Privileges[1].Luid ) )
err;

tkp.PrivilegeCount = 2;
tkp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
tkp.Privileges[1].Attributes = SE_PRIVILEGE_ENABLED;

AdjustTokenPrivileges( hToken, FALSE, &tkp, sizeof tkp,
NULL, NULL );
}

int main( int argc, char *argv[] )
{
HANDLE fh;

if ( argc != 3 )
{
printf( "usage: lnw {file} {new_link_name}\n" );
return 1;
}
enableprivs();

fh = CreateFile( argv[1], GENERIC_WRITE, 0, NULL, OPEN_EXISTING,
FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_POSIX_SEMANTICS, NULL );
if ( fh == INVALID_HANDLE_VALUE || fh == NULL ) err;

static char buf1[MAX_PATH];
static wchar_t buf2[MAX_PATH * 2];
char *p;
void *ctx = NULL;
WIN32_STREAM_ID wsi;
DWORD numwritten;

GetFullPathName( argv[2], MAX_PATH, &buf1[0], &p );

wsi.dwStreamId = BACKUP_LINK;
wsi.dwStreamAttributes = 0;
wsi.dwStreamNameSize = 0;
wsi.Size.QuadPart = strlen( buf1 ) * 2 + 2;
MultiByteToWideChar( CP_ACP, 0, buf1, strlen( buf1 ) + 1, buf2, MAX_PATH );

if ( ! BackupWrite( fh, (byte *) &wsi, 20, &numwritten, FALSE, FALSE, &ctx )
)err;
if ( numwritten != 20 ) err;

if ( ! BackupWrite( fh, (byte *) buf2, wsi.Size.LowPart, &numwritten, FALSE,
FALSE, &ctx ) )err;
if ( numwritten != wsi.Size.LowPart )err;

BackupWrite( fh, (byte *) &buf1[0], 0, &numwritten, TRUE, FALSE, &ctx );
CloseHandle( fh );
return 0;
}