go-cat2 refactoring

go-cat2/main.go

@@ -1,54 +1,25 @@
 package main
 
-import "fmt"
 import "io"
 import "log"
 import "os"
-import "strings"
 
-var err error
 var reader io.Reader
 
-const BUFSIZE = 32 * 1024
-
-func openFile(path *string) *os.File {
-	f, err := os.Open(os.Args[1])
-	if err != nil {
-		log.Fatalln(err)
-	}
-	return f
-}
-
-func readMe(r io.Reader) {
-	var n int
-	buf := make([]byte, BUFSIZE)
-	for {
-		n, err = r.Read(buf)
-		if n == 0 || err == io.EOF {
-			break
-		}
-		if err != nil {
-			log.Fatalln("Read error", err)
-		}
-		fmt.Printf("%s", buf[:n])
-	}
-}
-
 func main() {
 	if len(os.Args) <= 1 {
-		var content string
+		reader = os.Stdin
-		if _, err := fmt.Scanln(&content); err != nil {
-			log.Fatalln(err)
-		}
-		reader = strings.NewReader(content)
 	} else {
 		readers := []io.Reader{}
 		for _, fname := range os.Args[1:] {
-			f := openFile(&fname)
+			if f, err := os.Open(fname); err != nil {
-			defer f.Close()
+				log.Fatalln(err)
-			readers = append(readers, f)
+			} else {
+				defer f.Close()
+				readers = append(readers, f)
+			}
 		}
 		reader = io.MultiReader(readers...)
 	}
-	readMe(reader)
+	io.Copy(os.Stdout, reader)
 }