(wait_reading_process_input): Fix previous change.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/process.c b/src/process.c
index bebfba77843..06edf7c5e84 100644
--- a/src/process.c
+++ b/src/process.c
@@ -2311,7 +2311,8 @@ wait_reading_process_input (time_limit, microsecs, read_kbd, do_display)
           XSETPROCESS (proc, wait_proc);
 
           /* Read data from the process, until we exhaust it.  */
-          while (nread = read_process_output (proc, XINT (wait_proc->infd)))
+          while (XINT (wait_proc->infd) >= 0
+                 && nread = read_process_output (proc, XINT (wait_proc->infd)))
             total_nread += nread;
           if (total_nread > 0 && do_display)
             redisplay_preserve_echo_area ();