diff --git a/Formula/h/heksa.rb b/Formula/h/heksa.rb
index 247071c35bc1e..c55351db9c159 100644
--- a/Formula/h/heksa.rb
+++ b/Formula/h/heksa.rb
@@ -30,19 +30,8 @@ def install
   end
 
   test do
-    require "pty"
-
-    r, _w, pid = PTY.spawn("#{bin}/heksa -l 16 -f asc -o no #{test_fixtures("test.png")}")
-
+    output = shell_output("#{bin}/heksa --limit 16 --format asc --offset-format no #{test_fixtures("test.png")}")
     # remove ANSI colors
-    begin
-      output = r.read.gsub(/\e\[([;\d]+)?m/, "")
-      assert_match(/^.PNG/, output)
-    rescue Errno::EIO
-      # GNU/Linux raises EIO when read is done on closed pty
-    end
-
-    Process.wait(pid)
-    assert_equal 0, $CHILD_STATUS.exitstatus
+    assert_match(/^\.PNG/, output.gsub(/\e\[([;\d]+)?m/, ""))
   end
 end