diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..53c37a1
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+dist
\ No newline at end of file
diff --git a/README.md b/README.md
index e69de29..d0eda72 100644
--- a/README.md
+++ b/README.md
@@ -0,0 +1 @@
+# Logging with color and format string
\ No newline at end of file
diff --git a/log.go b/log.go
index 44772dd..0e0bee4 100644
--- a/log.go
+++ b/log.go
@@ -81,6 +81,7 @@ type logger struct {
 	out io.Writer
 
 	formatter  *LogFormater
+	funcMap    template.FuncMap
 	err_tmpl   *template.Template
 	debug_tmpl *template.Template
 	warn_tmpl  *template.Template
@@ -116,15 +117,33 @@ func (l *logger) Sub(sys string) *logger {
 }
 
 func (l *logger) guessColor() {
+	l.color = true
 	if w, ok := l.out.(*os.File); !ok || os.Getenv("TERM") == "dumb" ||
 		(!isatty.IsTerminal(w.Fd()) && !isatty.IsCygwinTerminal(w.Fd())) {
 		l.color = false
 	}
+	if w, ok := l.err.(*os.File); !ok || os.Getenv("TERM") == "dumb" ||
+		(!isatty.IsTerminal(w.Fd()) && !isatty.IsCygwinTerminal(w.Fd())) {
+		l.color = false
+	}
 }
-func (l *logger) Color(c bool) {
+func (l *logger) SetColor(c bool) {
 	l.color = c
 }
 
+func (l *logger) SetErrOutput(err io.Writer) {
+	l.err = err
+}
+
+func (l *logger) SetOutput(out io.Writer) {
+	l.out = out
+}
+
+func (l *logger) Reload() error {
+	l.guessColor()
+	return l.ParseTmpl()
+}
+
 func NewLogFormater() *LogFormater {
 	return &LogFormater{
 		ErrTmplStr:   DEFAULT_ERR,
@@ -134,7 +153,7 @@ func NewLogFormater() *LogFormater {
 	}
 }
 
-func (l *logger) FuncMap() template.FuncMap {
+func (l *logger) DefaultFuncMap() template.FuncMap {
 	funcMap := template.FuncMap{
 		"Time": func() string { return time.Now().Format("2006/01/02 15:04:05") },
 	}
@@ -143,23 +162,25 @@ func (l *logger) FuncMap() template.FuncMap {
 }
 
 func (l *logger) ParseTmpl() error {
-	funcMap := l.FuncMap()
-	err_tmpl, err := template.New("err_tmpl").Funcs(funcMap).Parse(l.formatter.ErrTmplStr)
+	if l.funcMap == nil {
+		l.funcMap = l.DefaultFuncMap()
+	}
+	err_tmpl, err := template.New("err_tmpl").Funcs(l.funcMap).Parse(l.formatter.ErrTmplStr)
 	if err != nil {
 		return err
 	}
 	l.err_tmpl = err_tmpl
-	warn_tmpl, err := template.New("warn_tmpl").Funcs(funcMap).Parse(l.formatter.WarnTmplStr)
+	warn_tmpl, err := template.New("warn_tmpl").Funcs(l.funcMap).Parse(l.formatter.WarnTmplStr)
 	if err != nil {
 		return err
 	}
 	l.warn_tmpl = warn_tmpl
-	info_tmpl, err := template.New("info_tmpl").Funcs(funcMap).Parse(l.formatter.InfoTmplStr)
+	info_tmpl, err := template.New("info_tmpl").Funcs(l.funcMap).Parse(l.formatter.InfoTmplStr)
 	if err != nil {
 		return err
 	}
 	l.info_tmpl = info_tmpl
-	debug_tmpl, err := template.New("debug_tmpl").Funcs(funcMap).Parse(l.formatter.DebugTmplStr)
+	debug_tmpl, err := template.New("debug_tmpl").Funcs(l.funcMap).Parse(l.formatter.DebugTmplStr)
 	if err != nil {
 		return err
 	}
@@ -167,9 +188,11 @@ func (l *logger) ParseTmpl() error {
 	return nil
 }
 
-func (l *logger) SetTmpl(formatter *LogFormater) error {
+func (l *logger) SetTmpl(formatter *LogFormater, funcMap template.FuncMap) {
 	l.formatter = formatter
-	return l.ParseTmpl()
+	if funcMap != nil {
+		l.funcMap = funcMap
+	}
 }
 
 func (l *logger) output(t tout, depth int, stack string, fields H, v ...interface{}) {
diff --git a/log_test.go b/log_test.go
index 0cb7b26..b630231 100644
--- a/log_test.go
+++ b/log_test.go
@@ -1,6 +1,9 @@
 package log
 
-import "testing"
+import (
+	"os"
+	"testing"
+)
 
 func TestDev(t *testing.T) {
 	PROD = false
@@ -61,7 +64,30 @@ func TestCustTmpl(t *testing.T) {
 	CustFormater.InfoTmplStr = `{{Time}} [{{blue}}INFO {{reset}}]` +
 		`{{if .System}}({{cyan}}{{.System}}{{reset}}){{end}} ` +
 		`key: test, value:{{.Fields.Test}}{{"\n"}}`
-	l.SetTmpl(CustFormater)
+	l.SetTmpl(CustFormater, nil)
+	l.Reload()
+	l.Error("d", "sdf", "sdfsdf")
+	l.ErrorF(H{"Test": "set"}, "d", "sdf", "sdfsdf")
+	l.Debug("d", "sdf", "sdfsdf")
+	l.DebugF(H{"Test": "set"}, "d", "sdf", "sdfsdf")
+	l.Warn("d", "sdf", "sdfsdf")
+	l.WarnF(H{"Test": "set"}, "d", "sdf", "sdfsdf")
+	l.Info("d", "sdf", "sdfsdf")
+	l.InfoF(H{"Test": "set"}, "d", "sdf", "sdfsdf")
+}
+
+func TestToFile(t *testing.T) {
+	PROD = true
+	l := Sub("TestToFile")
+
+	f, err := os.OpenFile("dist/test.log", os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0666)
+	if err != nil {
+		t.Error(err)
+	}
+	l.SetOutput(f)
+	l.SetErrOutput(f)
+	l.Reload()
+
 	l.Error("d", "sdf", "sdfsdf")
 	l.ErrorF(H{"Test": "set"}, "d", "sdf", "sdfsdf")
 	l.Debug("d", "sdf", "sdfsdf")