iterate

go/mlr.go

@@ -1,14 +1,80 @@
 package main
 
 import (
-	//"fmt"
-	"containers"
+	// System:
+	"bufio"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"strings"
+
+	// Miller:
+	//"containers"
 )
 
-func main() {
-	lrec := containers.LrecAlloc()
-	lrec.Put("a", "foo")
-	lrec.Put("x", "3")
-	lrec.Put("y", "y")
-	lrec.Print()
+// ----------------------------------------------------------------
+// xxx to do: stdout/stderr w/ ternary on exitrc
+func usage() {
+	fmt.Fprintf(os.Stderr, "Usage: %s [options] {filenames ...}\n", os.Args[0])
+	//fmt.Fprintf(os.Stderr, "If no file name is given, or if filename is \"-\", stdin is used.\n", os.Args[0])
+	flag.PrintDefaults()
+	os.Exit(1)
+}
+
+// ----------------------------------------------------------------
+func main() {
+	// pFoo := flag.Bool("f", false, "Foo")
+
+	flag.Usage = usage
+	flag.Parse()
+	args := flag.Args()
+
+	// foo := *pFoo
+
+	if len(args) == 0 {
+		err := stream("-")
+		if err != nil {
+			log.Fatal(err)
+		}
+	} else {
+		for _, arg := range args {
+			err := stream(arg)
+			if err != nil {
+				log.Fatal(err)
+			}
+		}
+	}
+	os.Exit(0)
+}
+
+// ----------------------------------------------------------------
+func stream(sourceName string) error {
+	inputStream := os.Stdin
+	if sourceName != "-" {
+		var err error
+		if inputStream, err = os.Open(sourceName); err != nil {
+			return err
+		}
+	}
+
+	reader := bufio.NewReader(inputStream)
+
+	eof := false
+
+	for !eof {
+		line, err := reader.ReadString('\n')
+		if err == io.EOF {
+			err = nil
+			eof = true
+		} else if err != nil {
+			return err
+		} else {
+			// This is how to do a chomp:
+			line = strings.TrimRight(line, "\n")
+		}
+	}
+
+	return nil
 }