anchor.diff:          (with-c-environment (envp environment)
             (with-redirections ((infd outfd errfd) (file-actions stdin stdout stderr))
               (process-other-spawn-args attributes uid gid resetids current-directory)
  -            (if search
  -                (lfp-spawnp pid arg0 argv envp file-actions attributes)
  -                (lfp-spawn  pid arg0 argv envp file-actions attributes))
  +            (lfp-spawnp pid arg0 argv envp file-actions attributes)
               (make-instance 'process :pid (mem-ref pid 'pid-t)
                              :stdin infd :stdout outfd :stderr errfd)))))))
   
  -(defun run-program (program-and-args &key (search t) (environment t) (stderr t))
  +(defun run-program (program-and-args &key (environment t) (stderr t))
     (flet ((slurp (stream)
              (with-output-to-string (s)
                (loop :for c := (read-char stream nil nil)
                      :while c :do (write-char c s)))))
       (let ((process (create-process program-and-args
  -                                   :search search
                                      :environment environment
                                      :stdout :pipe
                                      :stderr (if stderr :pipe :stdout))))
  
positive.code: ;; program: :shell - the system shell
  ;;          file-path designator - a path
  ;; arguments: list
  ;; search: boolean. whether or not to search PROGRAM in $PATH when PROGRAM only names a file,
  ;;                  i.e., it's a relative path whose directory is NIL
  ;; environment: t - inherit environment
  ;;              nil - NULL environment
  ;;              alist - the environment to use
  
negative.code: ;; resetids: boolean - reset effective UID and GID to saved IDs
  ;; current-directory: path - a directory to switch to before executing
  
  (defun create-process (program-and-args &key (environment t)
                         (stdin t) (stdout t) (stderr t)
                         uid gid resetids current-directory)
    (destructuring-bind (program &rest arguments)
  