package main

import (
    "fmt"
    "os"
)

func main() {
    // 3.9 GB (4135698432 bytes)
    file := "/home/peter/ubuntu-9.10-dvd-i386.iso"
    flags := os.O_RDONLY
    perm := 0666
    in, err := os.Open(file, flags, perm)
    if err != nil {
        fmt.Println(file, err.String())
    }
    in.Close()
}

Go 40ce831c5918+ tip. Linux Ubuntu 9.10 386 32-bit.

The program fails to open the file if the file size is greater than or
equal to 2^31 bytes. strace shows:
open("/home/peter/ubuntu-9.10-dvd-i386.iso", O_RDONLY|O_CLOEXEC) = -1
EOVERFLOW (Value too large for defined data type).

If flags = flags | O_LARGEFILE the program opens the file.

The ioutil.ReadFile() implicit file open also fails for the same reason.

Go 9cf4bce3ad75+ tip. Linux Ubuntu 9.10 amd64 64-bit.

Program opens the file.