diff --git a/file.go b/file.go
new file mode 100644
index 0000000..4ef63cb
--- /dev/null
+++ b/file.go
@@ -0,0 +1,266 @@
+/*
+gg is a recursive grep written in Go, with some shortcuts for everyday use.
+*/
+package main
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+type notPlainTextBehaviour int
+
+const (
+	notPlainTextShort notPlainTextBehaviour = iota
+	notPlainTextFull
+	notPlainTextSkip
+)
+
+type notPlainTextFlag struct {
+	b notPlainTextBehaviour
+}
+
+func (nptf *notPlainTextFlag) String() string {
+	switch nptf.b {
+	case notPlainTextShort:
+		return "short"
+	case notPlainTextFull:
+		return "full"
+	case notPlainTextSkip:
+		return "skip"
+	}
+	return "???"
+}
+
+func (nptf *notPlainTextFlag) Set(s string) error {
+	switch s {
+	case "short":
+		nptf.b = notPlainTextShort
+	case "full":
+		nptf.b = notPlainTextFull
+	case "skip":
+		nptf.b = notPlainTextSkip
+	default:
+		return errors.New("must be one of short|full|skip")
+	}
+	return nil
+}
+
+func (nptf *notPlainTextFlag) Type() string {
+	return "short|full|skip" // ???
+}
+
+func file(path string, data []byte) {
+	var short string
+	switch {
+	case isBinary(data):
+		switch binaryFile.b {
+		case notPlainTextShort:
+			short = "Binary"
+		case notPlainTextSkip:
+			return
+		}
+
+	case isMinified(data):
+		switch minifiedFile.b {
+		case notPlainTextShort:
+			short = "Minified"
+		case notPlainTextSkip:
+			return
+		}
+	}
+
+	var (
+		lineNum       int
+		printedHeader bool
+		b, b2         strings.Builder
+	)
+
+	// split into lines
+	for len(data) > 0 {
+		eol := bytes.IndexByte(data, '\n')
+		lineNum++
+		var line []byte
+		if eol == -1 {
+			line = data
+			data = nil
+		} else {
+			line = data[:eol]
+			data = data[eol+1:]
+		}
+
+		loc := findMatches(line)
+		if loc == nil {
+			continue
+		}
+
+		switch {
+		case !printedHeader && short != "":
+			if printedFull {
+				fmt.Println("")
+				printedFull = false
+			}
+			fmt.Printf("%s file %s matches.\n", short, path)
+			return
+
+		case !printedHeader:
+			if printedFull {
+				fmt.Println("")
+			}
+			printedFull = true
+			fmt.Println(display.Filename(path))
+			printedHeader = true
+		}
+
+		b.Reset()
+		fmt.Fprintf(&b, "%4d: ", display.LineNumber(lineNum))
+
+		if loc[0] < 128 {
+			escape(&b, line[0:loc[0]])
+		} else {
+			start := loc[0] - 128
+			for i := 0; i < 5; i++ {
+				if utf8.RuneStart(line[start]) {
+					break
+				}
+				start++
+			}
+
+			b.WriteString(display.TruncatedBytes(start).String())
+			b.WriteString(display.TruncatedMarker().String())
+			escape(&b, line[start:loc[0]])
+		}
+
+		if loc[1]-loc[0] < 128 {
+			b2.Reset()
+			escape(&b2, line[loc[0]:loc[1]])
+			b.WriteString(display.Match(b2.String()).String())
+
+			if loc[1]+128 > len(line) {
+				escape(&b, line[loc[1]:])
+			} else {
+				end := loc[1] + 128
+				for i := 0; i < 5; i++ {
+					if utf8.RuneStart(line[end]) {
+						break
+					}
+					end--
+				}
+				escape(&b, line[loc[1]:end])
+				b.WriteString(display.TruncatedBytes(len(line) - end).String())
+				b.WriteString(display.TruncatedMarker().String())
+			}
+
+		} else {
+			end := loc[1]
+			for i := 0; i < 5; i++ {
+				if utf8.RuneStart(line[end]) {
+					break
+				}
+				end--
+			}
+
+			b2.Reset()
+			escape(&b2, line[loc[0]:end])
+			b.WriteString(display.Match(b2.String()).String())
+			b.WriteString(display.TruncatedMarker().String())
+			b.WriteString(display.TruncatedBytes(len(line) - end).String())
+
+		}
+
+		b.WriteRune('\n')
+		fmt.Print(b.String())
+	}
+}
+
+func isBinary(data []byte) bool {
+	bytesToExamine := 4096
+
+	for bytesToExamine > 0 {
+		r, s := utf8.DecodeRune(data)
+		switch {
+		case s == 0:
+			// end of string
+			return false
+		case s == 1 && r == utf8.RuneError:
+			// invalid UTF-8
+			return true
+		case r == '\r', r == '\n', r == '\t':
+			// valid control chars
+		case r < ' ':
+			// invalid control chars
+			return true
+		}
+		data = data[s:]
+		bytesToExamine -= s
+	}
+
+	return false
+}
+
+func isMinified(data []byte) bool {
+	const longLine = 256
+	bytesToExamine := 4096
+	var lineLength int
+
+	for bytesToExamine > 0 {
+		r, s := utf8.DecodeRune(data)
+		switch {
+		case s == 0:
+			// end of string
+			return false
+		case r == '\n':
+			lineLength = 0
+		default:
+			lineLength++
+			if lineLength >= longLine {
+				return true
+			}
+		}
+		data = data[s:]
+		bytesToExamine -= s
+	}
+	return false
+}
+
+func findMatches(data []byte) (loc []int) {
+	for _, re := range regexps {
+		loc := re.FindIndex(data)
+		if loc != nil {
+			return loc
+		}
+	}
+	for _, s := range searchBytes {
+		pos := bytes.Index(data, s)
+		if pos != -1 {
+			return []int{pos, pos + len(s)}
+		}
+	}
+	return nil
+}
+
+func escape(b *strings.Builder, s []byte) {
+	for len(s) > 0 {
+		r, size := utf8.DecodeRune(s)
+		s = s[size:]
+
+		switch {
+		case r == utf8.RuneError && size == 1:
+			b.WriteString(display.BadUTF8Char().String())
+
+		case r == '\r':
+			b.WriteString(display.CarriageReturn().String())
+
+		case r == '\t',
+			unicode.IsPrint(r):
+			b.WriteRune(r)
+
+		default:
+			b.WriteString(display.UnprintableChar().String())
+		}
+	}
+}
diff --git a/main.go b/main.go
index 48ce67d..5a93986 100644
--- a/main.go
+++ b/main.go
@@ -4,15 +4,10 @@ gg is a recursive grep written in Go, with some shortcuts for everyday use.
 package main
 
 import (
-	"bytes"
 	"errors"
-	"fmt"
 	"os"
 	"path/filepath"
 	"regexp"
-	"strings"
-	"unicode"
-	"unicode/utf8"
 
 	"github.com/spf13/cobra"
 	"golang.org/x/sys/unix"
@@ -20,8 +15,6 @@ import (
 
 // TODO:
 //  - bold of escaped output doesn't work
-//  - binary file detection
-//  - long-line / minified-file detection
 //  - ignore files by extension (or glob?)
 
 func main() {
@@ -61,11 +54,13 @@ var (
 	searchBytes  [][]byte
 	searchPath   []string
 	ignoreList   []string
+	binaryFile   notPlainTextFlag
+	minifiedFile notPlainTextFlag
 	ignoreMap    map[string]struct{}
 	ignoreCase   bool
 	noColour     bool
 	display      *Display
-	matchedAny   bool
+	printedFull  bool
 )
 
 func init() {
@@ -74,6 +69,8 @@ func init() {
 	rootCmd.Flags().StringSliceVarP(&ignoreList, "exclude", "x", []string{".git"}, "files/directories to exclude")
 	rootCmd.Flags().BoolVarP(&ignoreCase, "ignore-case", "i", false, "make all searches case insensitive")
 	rootCmd.Flags().BoolVarP(&noColour, "no-colour", "C", false, "disable colour output")
+	rootCmd.Flags().Var(&binaryFile, "binary", "what to do with binary files")
+	rootCmd.Flags().Var(&minifiedFile, "minified", "what to do with minified text files")
 }
 
 func run(c *cobra.Command, args []string) error {
@@ -164,147 +161,12 @@ func search(path string) error {
 		return err
 	}
 	defer f.Close()
-	fullData, err := unix.Mmap(int(f.Fd()), 0, int(st.Size()), unix.PROT_READ, unix.MAP_PRIVATE)
+	data, err := unix.Mmap(int(f.Fd()), 0, int(st.Size()), unix.PROT_READ, unix.MAP_PRIVATE)
 	if err != nil {
 		return err
 	}
-	defer unix.Munmap(fullData)
-
-	var printedHeader bool
-
-	var (
-		data    = fullData
-		lineNum int
-		b, b2   strings.Builder
-	)
-	for len(data) > 0 {
-		eol := bytes.IndexByte(data, '\n')
-		lineNum++
-		var line []byte
-		if eol == -1 {
-			line = data
-			data = nil
-		} else {
-			line = data[:eol]
-			data = data[eol+1:]
-		}
-
-		if len(line) == 0 {
-			continue
-		}
-
-		loc := matches(line)
-		if loc == nil {
-			continue
-		}
-
-		if !printedHeader {
-			printedHeader = true
-			if !matchedAny {
-				matchedAny = true
-			} else {
-				fmt.Println("")
-			}
-			fmt.Println(display.Filename(path))
-		}
-
-		b.Reset()
-		fmt.Fprintf(&b, "%4d: ", display.LineNumber(lineNum))
-
-		if loc[0] < 128 {
-			escape(&b, line[0:loc[0]])
-		} else {
-			start := loc[0] - 128
-			for i := 0; i < 5; i++ {
-				if utf8.RuneStart(line[start]) {
-					break
-				}
-				start++
-			}
-
-			b.WriteString(display.TruncatedBytes(start).String())
-			b.WriteString(display.TruncatedMarker().String())
-			escape(&b, line[start:loc[0]])
-		}
-
-		if loc[1]-loc[0] < 128 {
-			b2.Reset()
-			escape(&b2, line[loc[0]:loc[1]])
-			b.WriteString(display.Match(b2.String()).String())
-
-			if loc[1]+128 > len(line) {
-				escape(&b, line[loc[1]:])
-			} else {
-				end := loc[1] + 128
-				for i := 0; i < 5; i++ {
-					if utf8.RuneStart(line[end]) {
-						break
-					}
-					end--
-				}
-				escape(&b, line[loc[1]:end])
-				b.WriteString(display.TruncatedBytes(len(line) - end).String())
-				b.WriteString(display.TruncatedMarker().String())
-			}
-
-		} else {
-			end := loc[1]
-			for i := 0; i < 5; i++ {
-				if utf8.RuneStart(line[end]) {
-					break
-				}
-				end--
-			}
-
-			b2.Reset()
-			escape(&b2, line[loc[0]:end])
-			b.WriteString(display.Match(b2.String()).String())
-			b.WriteString(display.TruncatedMarker().String())
-			b.WriteString(display.TruncatedBytes(len(line) - end).String())
-
-		}
-
-		b.WriteRune('\n')
-		fmt.Print(b.String())
-	}
+	defer unix.Munmap(data)
 
+	file(path, data)
 	return nil
 }
-
-func matches(data []byte) (loc []int) {
-	for _, re := range regexps {
-		loc := re.FindIndex(data)
-		if loc != nil {
-			return loc
-		}
-	}
-	for _, s := range searchBytes {
-		pos := bytes.Index(data, s)
-		if pos != -1 {
-			return []int{pos, pos + len(s)}
-		}
-	}
-	return nil
-}
-
-func escape(b *strings.Builder, s []byte) {
-	for len(s) > 0 {
-		r, size := utf8.DecodeRune(s)
-		s = s[size:]
-
-		switch {
-		case r == utf8.RuneError && size == 1:
-			b.WriteString(display.BadUTF8Char().String())
-
-		case r == '\r':
-			b.WriteString(display.CarriageReturn().String())
-
-		case r == '\t',
-			unicode.IsPrint(r):
-			b.WriteRune(r)
-
-		default:
-			b.WriteString(display.UnprintableChar().String())
-		}
-	}
-}