std/os

import "github.com/eugenioenko/goalchemy/std/os"

Package os reads and writes whole files on the host file system. Errors are *PathError values whose Err matches ErrNotExist, ErrExist, ErrPermission or errors.ErrUnsupported through errors.Is, as in Go. Hosts without a file system, such as browsers, fail every call with an error matching errors.ErrUnsupported.

const MaxFileBytes = os.MaxFileBytes

MaxFileBytes is the largest file ReadFile returns and WriteFile accepts.

var (
  ErrInvalid    = errors.New("invalid argument")
  ErrPermission = errors.New("permission denied")
  ErrExist      = errors.New("file already exists")
  ErrNotExist   = errors.New("file does not exist")
)

Portable analogs of the io/fs errors.

ReadFile

func ReadFile(name string) ([]byte, error)

ReadFile reads the named file and returns its contents. A directory fails with op “read”, as on Linux; other failures use op “open”.

WriteFile

func WriteFile(name string, data []byte, perm FileMode) error

WriteFile writes data to the named file, creating it if necessary. If the file does not exist, WriteFile creates it with permissions perm (before the umask); otherwise WriteFile truncates it before writing, without changing permissions.

type FileMode

type FileMode uint32

A FileMode holds permission bits; only the low nine bits are applied.

type PathError

type PathError struct {
  Op   string
  Path string
  Err  error
}

PathError records an error and the operation and file path that caused it.

PathError.Error

func (e *PathError) Error() string

PathError.Unwrap

func (e *PathError) Unwrap() error