Force line-buffered progress during svn export

svn_interact/svn_git_init

@@ -7,7 +7,15 @@ echo "Exporting SVN working copy to $DEST (versioned files only)..."
 rm -rf -- "$DEST"
 count=0
 start_ts="$(date +%s.%N)"
-svn export . "$DEST" | awk -v start="$start_ts" '
+if command -v stdbuf >/dev/null 2>&1; then
+  export_cmd=(stdbuf -oL svn export . "$DEST")
+  awk_cmd=(stdbuf -o0 awk -v start="$start_ts")
+else
+  export_cmd=(svn export . "$DEST")
+  awk_cmd=(awk -W interactive -v start="$start_ts")
+fi
+
+"${export_cmd[@]}" | "${awk_cmd[@]}" '
   function elapsed() {
     cmd = "date +%s.%N"
     cmd | getline now