help and README

src/main.zig

@@ -4,9 +4,11 @@ const stdout = std.io.getStdOut().writer();
 const Base64 = @import("base64.zig");
 
 const usageText =
-    \\Usage: baze64 {-d/-D} input
+    \\Usage: baze64 {-d/-D} {-h/-H} input
+    \\With no arguments, encodes input into a base64 string
     \\Args:
-    \\  -d -D: decode instead of encode
+    \\  -d -D: decodes a base64 string
+    \\  -h -H: print this help
     ;
 
 
@@ -33,6 +35,9 @@ pub fn main() !void {
 
         if (std.mem.eql(u8, arg, "-d") or std.mem.eql(u8, arg, "-D")) {
             decodeSwitch = true;
+        } else if (std.mem.eql(u8, arg, "-h") or std.mem.eql(u8, arg, "-H")) {
+            try stdout.print("{s}\n", .{usageText});
+            std.process.exit(0);
         } else {
             input = arg;
             break;