master a5b24a0 2/4: Revert "Remove compat code from comint.el"

[Lars Ingebrigtsen]

branch: master
commit a5b24a0c44dd603942c8cf531b47a3905927d3f4
Author: Lars Ingebrigtsen <larsi@gnus.org>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Revert "Remove compat code from comint.el"
    
    This reverts commit 4d00db5538dc0ef47cf1cdf425b895d04145fe9e.
    
    We still have Emacs builds on systems with no multi-taskin.
---
 lisp/comint.el | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lisp/comint.el b/lisp/comint.el
index 843cba1..df947b9 100644
--- a/lisp/comint.el
+++ b/lisp/comint.el
@@ -735,6 +735,8 @@ contents are sent to the process as its initial input.
 If PROGRAM is a string, any more args are arguments to PROGRAM.
 
 Return the (possibly newly created) process buffer."
+  (or (fboundp 'start-file-process)
+      (error "Multi-processing is not supported for this system"))
   (setq buffer (get-buffer-create (or buffer (concat "*" name "*"))))
   ;; If no process, or nuked process, crank up a new one and put buffer in
   ;; comint mode.  Otherwise, leave buffer and existing process alone.