Add -b output binary option

Changes.md

@@ -1,5 +1,7 @@
 ## v1.7.1 (2024-??-??)
 - [bug] Fix `cppo -version`, which used to print a blank line (#92).
+- [+ui] Added the `-b` output binary option so that Windows does
+        not add CRLF endings.
 
 ## v1.7.0 (2024-08-22)
 - [+ui] Multi-line macros, without line terminators `\`,

src/cppo_main.ml

@@ -78,6 +78,7 @@ let main () =
   let preserve_quotations = ref false in
   let show_exact_locations = ref false in
   let show_no_locations = ref false in
+  let output_binary = ref false in
   let options = [
     "-D", Arg.String (fun s -> header := ("#define " ^ s ^ "\n") :: !header),
     "DEF
@@ -133,6 +134,10 @@ let main () =
           Do not output any line directive other than those found in the
           input (overrides -s).";
 
+    "-b", Arg.Set output_binary,
+    "
+          Write output without CRLF normalization on Windows.";
+
     "-version", Arg.Unit (fun () ->
                             print_endline Cppo_version.cppo_version;
                             exit 0),
@@ -215,7 +220,10 @@ Options:" Sys.argv.(0) in
         print_string (Buffer.contents buf);
         flush stdout
     | Some file ->
-        let oc = open_out file in
+        let oc =
+          if !output_binary then open_out_bin file
+          else open_out file
+        in
         output_string oc (Buffer.contents buf);
         close_out oc