diff --git a/doc/man_docs.go b/doc/man_docs.go
index 8c7fba44..817070f9 100644
--- a/doc/man_docs.go
+++ b/doc/man_docs.go
@@ -139,25 +139,25 @@ func fillHeader(header *GenManHeader, name string) error {
 	return nil
 }
 
-func manPreamble(buf *bytes.Buffer, header *GenManHeader, cmd *cobra.Command, dashedName string) {
+func manPreamble(buf io.StringWriter, header *GenManHeader, cmd *cobra.Command, dashedName string) {
 	description := cmd.Long
 	if len(description) == 0 {
 		description = cmd.Short
 	}
 
-	buf.WriteString(fmt.Sprintf(`%% %s(%s)%s
+	wrStringAndCheck(buf, fmt.Sprintf(`%% %s(%s)%s
 %% %s
 %% %s
 # NAME
 `, header.Title, header.Section, header.date, header.Source, header.Manual))
-	buf.WriteString(fmt.Sprintf("%s \\- %s\n\n", dashedName, cmd.Short))
-	buf.WriteString("# SYNOPSIS\n")
-	buf.WriteString(fmt.Sprintf("**%s**\n\n", cmd.UseLine()))
-	buf.WriteString("# DESCRIPTION\n")
-	buf.WriteString(description + "\n\n")
+	wrStringAndCheck(buf, fmt.Sprintf("%s \\- %s\n\n", dashedName, cmd.Short))
+	wrStringAndCheck(buf, "# SYNOPSIS\n")
+	wrStringAndCheck(buf, fmt.Sprintf("**%s**\n\n", cmd.UseLine()))
+	wrStringAndCheck(buf, "# DESCRIPTION\n")
+	wrStringAndCheck(buf, description+"\n\n")
 }
 
-func manPrintFlags(buf *bytes.Buffer, flags *pflag.FlagSet) {
+func manPrintFlags(buf io.StringWriter, flags *pflag.FlagSet) {
 	flags.VisitAll(func(flag *pflag.Flag) {
 		if len(flag.Deprecated) > 0 || flag.Hidden {
 			return
@@ -181,22 +181,22 @@ func manPrintFlags(buf *bytes.Buffer, flags *pflag.FlagSet) {
 			format += "]"
 		}
 		format += "\n\t%s\n\n"
-		buf.WriteString(fmt.Sprintf(format, flag.DefValue, flag.Usage))
+		wrStringAndCheck(buf, fmt.Sprintf(format, flag.DefValue, flag.Usage))
 	})
 }
 
-func manPrintOptions(buf *bytes.Buffer, command *cobra.Command) {
+func manPrintOptions(buf io.StringWriter, command *cobra.Command) {
 	flags := command.NonInheritedFlags()
 	if flags.HasAvailableFlags() {
-		buf.WriteString("# OPTIONS\n")
+		wrStringAndCheck(buf, "# OPTIONS\n")
 		manPrintFlags(buf, flags)
-		buf.WriteString("\n")
+		wrStringAndCheck(buf, "\n")
 	}
 	flags = command.InheritedFlags()
 	if flags.HasAvailableFlags() {
-		buf.WriteString("# OPTIONS INHERITED FROM PARENT COMMANDS\n")
+		wrStringAndCheck(buf, "# OPTIONS INHERITED FROM PARENT COMMANDS\n")
 		manPrintFlags(buf, flags)
-		buf.WriteString("\n")
+		wrStringAndCheck(buf, "\n")
 	}
 }
 
diff --git a/doc/man_docs_test.go b/doc/man_docs_test.go
index 2c400f5d..609afdc6 100644
--- a/doc/man_docs_test.go
+++ b/doc/man_docs_test.go
@@ -131,7 +131,7 @@ func TestGenManSeeAlso(t *testing.T) {
 func TestManPrintFlagsHidesShortDeperecated(t *testing.T) {
 	c := &cobra.Command{}
 	c.Flags().StringP("foo", "f", "default", "Foo flag")
-	c.Flags().MarkShorthandDeprecated("foo", "don't use it no more")
+	er(c.Flags().MarkShorthandDeprecated("foo", "don't use it no more"))
 
 	buf := new(bytes.Buffer)
 	manPrintFlags(buf, c.Flags())
diff --git a/doc/man_examples_test.go b/doc/man_examples_test.go
index d056d253..58dee8a8 100644
--- a/doc/man_examples_test.go
+++ b/doc/man_examples_test.go
@@ -21,7 +21,7 @@ func ExampleGenManTree() {
 		Title:   "MINE",
 		Section: "3",
 	}
-	doc.GenManTree(cmd, header, "/tmp")
+	er(doc.GenManTree(cmd, header, "/tmp"))
 }
 
 func ExampleGenMan() {
@@ -34,6 +34,6 @@ func ExampleGenMan() {
 		Section: "3",
 	}
 	out := new(bytes.Buffer)
-	doc.GenMan(cmd, header, out)
+	er(doc.GenMan(cmd, header, out))
 	fmt.Print(out.String())
 }