Golang Windows Memory File mapping

This is a creation in Article, where the information may have evolved or changed.

Windows implements the memory file mapping, Golang is actually called the Windows API, and Win32 programming no GOD horse difference.

FD, Err: = Syscall. Open ("./111.csv", Syscall. Generic_all, 0)
Defer syscall. Close (FD)

Fsize, err: = Syscall. Seek (FD, 0, 2)
Syscall. Seek (FD, 0, 0)
Number of pages per block
var pagesperblock int64 = 8192
Number of data blocks
var blocksize int64 = Int64 (Syscall. GetPageSize ()) * Pagesperblock
var blocknum int64 = Fsize/blocksize
If fsize%blocksize > 0 {
Blocknum = blocknum + 1
}
Hmap, err: = Syscall. CreateFileMapping (FD, Nil, syscall. Page_readonly, UInt32 (fsize>>32), UInt32 (fsize), nil)
Defer syscall. CloseHandle (HMAP)

var tmbgn = time. Now ()

Fmt. Println ("blocknum=", Blocknum)
var i int64
For i = 0; i < Blocknum; i++ {
var datalen int32 = Int32 (BlockSize)
if i = = (blocknum-1) {
Datalen = Int32 (fsize% blocksize)
}
Fmt. Println ("datalen=", Datalen)
Start reading memory block
var Currpos int64 = i * blocksize

var Tmplen int = int (datalen)

Addr, err: = Syscall. MapViewOfFile (Hmap, Syscall. File_map_read, 0, UInt32 (currpos), UIntPtr (Tmplen))

Defer syscall. UnmapViewOfFile (addr)
Turn addr into slice.
D: = (*[1 << 28]byte) (unsafe. Pointer (addr))
T: = D[:tmplen]
Processing Data T
}