Merge from origin/emacs-26

8fbe462 (origin/emacs-26) ; * doc/lispref/positions.texi (List Motion...
1d9efc0 Add index for "\( in strings" (Bug#25195)
304e96f Fix doc-string of 'fit-window-to-buffer' (Bug#36848)
d4c4987 Update view-mode docstring
d6ca1fc ; * lisp/term.el: Add missing / to esc seq commentary.
b3e2073 Fix subproc listening when setting filter to non-t (Bug#36591)
f671950 * etc/NEWS.25: Belatedly announce rcirc-reconnect-delay.
7f42277 Mention term.el's \032 dir tracking in commentary (Bug#19524)
16a529e Remove upload functionality of package-x from the elisp manual
78e6c2a * etc/AUTHORS: Update.
086a56e Clarify Gravatar docs
0592467 * doc/lispref/display.texi (Defining Faces): Say a face can't...

# Conflicts:
#	doc/emacs/programs.texi
#	etc/AUTHORS
#	lisp/term.el

1 files changed, 12 insertions, 3 deletions

diff --git a/src/process.c b/src/process.c
index abadabe77ea..066edbc83d6 100644
--- a/src/process.c
+++ b/src/process.c
@@ -1279,10 +1279,19 @@ The string argument is normally a multibyte string, except:
   if (NILP (filter))
     filter = Qinternal_default_process_filter;
 
-  pset_filter (p, filter);
-
   if (p->infd >= 0)
-    set_process_filter_masks (p);
+    {
+      /* If filter WILL be t, stop reading output.  */
+      if (EQ (filter, Qt) && !EQ (p->status, Qlisten))
+        delete_read_fd (p->infd);
+      else if (/* If filter WAS t, then resume reading output.  */
+               EQ (p->filter, Qt)
+               /* Network or serial process not stopped:  */
+               && !EQ (p->command, Qt))
+        add_process_read_fd (p->infd);
+    }
+
+  pset_filter (p, filter);
 
   if (NETCONN1_P (p) || SERIALCONN1_P (p) || PIPECONN1_P (p))
     pset_childp (p, Fplist_put (p->childp, QCfilter, filter));