-- testing read-write-loop/fd --------------------------------------------
    giving offsets ................................................... [ PASS]
    giving size ...................................................... [ PASS]
    giving size and offset ........................................... [ERROR]
        
Error: (open-input-file) cannot open file - No such file or directory: "/tmp/sendfile-test.data.out"
    (begin
      (with-prepared-environment
        offset-test-file
        (lambda (in out)
          (parameterize
            ((force-implementation 'read-write))
            (sendfile in out offset: 213 bytes: 15)))
        #t)
      (file-contents test-file-out))
    3 tests completed in 0.003 seconds.
    1 error (33.3%).
    2 out of 3 (66.7%) tests passed.
    -- done testing read-write-loop/fd ---------------------------------------

;;;
;;; The previous error was on linux/x86.  This one is on linux/x86_64
;;;


    -- testing read-write-loop/port ------------------------------------------
    giving offsets ................................................... [ PASS]
    giving size ...................................................... [ FAIL]
        expected " Scheme occupies a unique niche." but got ""
    (begin
      (with-prepared-environment
        offset-test-file
        (lambda (in out)
          (parameterize
            ((force-implementation 'read-write-port))
            (sendfile in out bytes: 32)))
        #t
        #f)
      (file-contents test-file-out))
    giving size and offset ........................................... [ FAIL]
        expected "It is a mindset" but got ""
    (begin
      (with-prepared-environment
        offset-test-file
        (lambda (in out)
          (parameterize
            ((force-implementation 'read-write-port))
            (sendfile in out offset: 213 bytes: 15)))
        #t
        #f)
      (file-contents test-file-out))
    3 tests completed in 0.001 seconds.
    2 failures (66.7%).
    1 out of 3 (33.3%) test passed.
    -- done testing read-write-loop/port -------------------------------------