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nf/cat.coffee

Forked from anonymous/cat.coffee
Created September 10, 2011 09:48
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Revisions

  1. nf revised this gist Sep 10, 2011. 1 changed file with 17 additions and 101 deletions.
    118 changes: 17 additions & 101 deletions cat.go
    View file
    Original file line number Diff line number Diff line change
    @@ -1,111 +1,27 @@
    package main

    import (
    "fmt"
    "os"
    "syscall"
    "io"
    "log"
    "os"
    )

    type File struct {
    fd int // file descriptor number
    name string // file name at Open time
    }

    func OpenFile(name string, mode int, perm uint32) (file *File, err os.Error) {
    r, e := syscall.Open(name, mode, perm)
    if e != 0 {
    err = os.Errno(e)
    }
    return newFile(r, name), err
    }

    const (
    O_RDONLY = syscall.O_RDONLY
    O_RDWR = syscall.O_RDWR
    O_CREATE = syscall.O_CREAT
    O_TRUNC = syscall.O_TRUNC
    )

    func Open(name string) (file *File, err os.Error) {
    return OpenFile(name, O_RDONLY, 0)
    }

    func (file *File) Close() os.Error {
    if file == nil {
    return os.EINVAL
    }
    e := syscall.Close(file.fd)
    file.fd = -1 // so it can't be closed again
    if e != 0 {
    return os.Errno(e)
    }
    return nil
    }

    func (file *File) Read(b []byte) (ret int, err os.Error) {
    if file == nil {
    return -1, os.EINVAL
    }
    r, e := syscall.Read(file.fd, b)
    if e != 0 {
    err = os.Errno(e)
    }
    return int(r), err
    }

    func (file *File) Write(b []byte) (ret int, err os.Error) {
    if file == nil {
    return -1, os.EINVAL
    }
    r, e := syscall.Write(file.fd, b)
    if e != 0 {
    err = os.Errno(e)
    }
    return int(r), err
    }

    func (file *File) String() string {
    return file.name
    }

    func newFile(fd int, name string) *File {
    if fd < 0 {
    return nil
    }
    return &File{fd, name}
    }

    var (
    Stdin = newFile(syscall.Stdin, "/dev/stdin")
    Stdout = newFile(syscall.Stdout, "/dev/stdout")
    Stderr = newFile(syscall.Stderr, "/dev/stderr")
    )

    func cat(f *File) {
    const NBUF = 512
    var buf [NBUF]byte
    for {
    switch nr, er := f.Read(buf[:]); true {
    case nr < 0:
    fmt.Fprintf(os.Stderr, "cat: error reading from %s: %s\n", f.String(), er.String())
    os.Exit(1)
    case nr == 0: // EOF
    return
    case nr > 0:
    if nw, ew := Stdout.Write(buf[0:nr]); nw != nr {
    fmt.Fprintf(os.Stderr, "cat: error writing from %s: %s\n", f.String(), ew.String())
    os.Exit(1)
    }
    func cat(name string) os.Error {
    f, err := os.Open(name)
    if err != nil {
    return err
    }
    }
    defer f.Close()
    if _, err = io.Copy(os.Stdout, f); err != nil {
    return err
    }
    return nil
    }

    func main() {
    f, err := Open("file.txt")
    if f == nil {
    fmt.Fprintf(os.Stderr, "cat: can't open %s: error %s\n", "file.txt", err)
    os.Exit(1)
    }
    cat(f)
    f.Close()
    for _, arg := range os.Args[1:] {
    if err := cat(arg); err != nil {
    log.Print(err)
    }
    }
    }
  2. @invalid-email-address Anonymous created this gist Sep 10, 2011.
    12 changes: 12 additions & 0 deletions cat.coffee
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,12 @@
    fs = require 'fs'

    class File
    constructor: (@name) ->
    read: (cb) ->
    fs.readFile @name, (err, code) ->
    throw err if err
    cb code.toString()

    file = new File "file.txt"
    file.read (contents) ->
    console.log contents
    111 changes: 111 additions & 0 deletions cat.go
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,111 @@
    package main

    import (
    "fmt"
    "os"
    "syscall"
    )

    type File struct {
    fd int // file descriptor number
    name string // file name at Open time
    }

    func OpenFile(name string, mode int, perm uint32) (file *File, err os.Error) {
    r, e := syscall.Open(name, mode, perm)
    if e != 0 {
    err = os.Errno(e)
    }
    return newFile(r, name), err
    }

    const (
    O_RDONLY = syscall.O_RDONLY
    O_RDWR = syscall.O_RDWR
    O_CREATE = syscall.O_CREAT
    O_TRUNC = syscall.O_TRUNC
    )

    func Open(name string) (file *File, err os.Error) {
    return OpenFile(name, O_RDONLY, 0)
    }

    func (file *File) Close() os.Error {
    if file == nil {
    return os.EINVAL
    }
    e := syscall.Close(file.fd)
    file.fd = -1 // so it can't be closed again
    if e != 0 {
    return os.Errno(e)
    }
    return nil
    }

    func (file *File) Read(b []byte) (ret int, err os.Error) {
    if file == nil {
    return -1, os.EINVAL
    }
    r, e := syscall.Read(file.fd, b)
    if e != 0 {
    err = os.Errno(e)
    }
    return int(r), err
    }

    func (file *File) Write(b []byte) (ret int, err os.Error) {
    if file == nil {
    return -1, os.EINVAL
    }
    r, e := syscall.Write(file.fd, b)
    if e != 0 {
    err = os.Errno(e)
    }
    return int(r), err
    }

    func (file *File) String() string {
    return file.name
    }

    func newFile(fd int, name string) *File {
    if fd < 0 {
    return nil
    }
    return &File{fd, name}
    }

    var (
    Stdin = newFile(syscall.Stdin, "/dev/stdin")
    Stdout = newFile(syscall.Stdout, "/dev/stdout")
    Stderr = newFile(syscall.Stderr, "/dev/stderr")
    )

    func cat(f *File) {
    const NBUF = 512
    var buf [NBUF]byte
    for {
    switch nr, er := f.Read(buf[:]); true {
    case nr < 0:
    fmt.Fprintf(os.Stderr, "cat: error reading from %s: %s\n", f.String(), er.String())
    os.Exit(1)
    case nr == 0: // EOF
    return
    case nr > 0:
    if nw, ew := Stdout.Write(buf[0:nr]); nw != nr {
    fmt.Fprintf(os.Stderr, "cat: error writing from %s: %s\n", f.String(), ew.String())
    os.Exit(1)
    }
    }
    }
    }

    func main() {
    f, err := Open("file.txt")
    if f == nil {
    fmt.Fprintf(os.Stderr, "cat: can't open %s: error %s\n", "file.txt", err)
    os.Exit(1)
    }
    cat(f)
    f.Close()
    }