~henesy/runez2: allow runez2 to use in/out files as arguments

2 files changed, 32 insertions(+), 3 deletions(-)

M README.md
M main.go

M README.md => README.md +1 -1

@@ 12,7 12,7 @@ See [the spec](./spec.md) for implementation details, or read the source ☺.
 
 ## Usage
 
-	runez2 [-D] [-c | -d] < input > output
+	runez2 [-D] [-c ¦ -d] [input ¦ < input] [output ¦ > output]
 
 ## Examples

M main.go => main.go +31 -2

@@ 35,9 35,38 @@ func main() {
 	}
 
 	// TODO - allow calling like `runez2 -c foo.txt` ;; use flag.Args
+	inf := os.Stdin
+	outf := os.Stdout
+
+	args := flag.Args()
+	switch len(args) {
+	case 0:
+	case 1:
+		f, err := os.OpenFile(args[0], os.O_RDONLY, 0755)
+		if err != nil {
+			fatal("err: could not read input file - ", err)
+		}
+
+		inf = f
+	case 2:
+		fin, err := os.OpenFile(args[0], os.O_RDONLY, 0755)
+		if err != nil {
+			fatal("err: could not read input file - ", err)
+		}
+
+		fout, err := os.OpenFile(args[1], os.O_RDWR|os.O_CREATE, 0755)
+		if err != nil {
+			fatal("err: could not read input file - ", err)
+		}
+
+		inf = fin
+		outf = fout
+	default:
+		fatal("err: invalid argument count; use stdin/stdout or specify in/out files")
+	}
 
-	in := bufio.NewReader(os.Stdin)
-	out := bufio.NewWriter(os.Stdout)
+	in := bufio.NewReader(inf)
+	out := bufio.NewWriter(outf)
 
 	// Choose mode operation
 	switch {