Functions

ssize_t pg_pread (int fd, void *buf, size_t size, off_t offset)

Function Documentation

◆ pg_pread()

ssize_t pg_pread ( int fd,

void * buf,

size_t size,

off_t offset

)

Definition at line 20 of file win32pread.c.

21{

22 OVERLAPPED overlapped = {0};

23 HANDLE handle;

24 DWORD result;

25

26 handle = (HANDLE) _get_osfhandle(fd);

27 if (handle == INVALID_HANDLE_VALUE)

28 {

29 errno = EBADF;

30 return -1;

31 }

32

33 /* Avoid overflowing DWORD. */

34 size = Min(size, 1024 * 1024 * 1024);

35

36 /* Note that this changes the file position, despite not using it. */

37 overlapped.Offset = offset;

38 if (!ReadFile(handle, buf, size, &result, &overlapped))

39 {

40 if (GetLastError() == ERROR_HANDLE_EOF)

41 return 0;

42

43 _dosmaperr(GetLastError());

44 return -1;

45 }

46

47 return result;

48}

Min

#define Min(x, y)

Definition: c.h:1003

buf

static char * buf

Definition: pg_test_fsync.c:72

fd

static int fd(const char *x, int i)

Definition: preproc-init.c:105

_dosmaperr

void _dosmaperr(unsigned long)

Definition: win32error.c:177

References _dosmaperr(), buf, fd(), and Min.