Don't retry reading after receiving EINVAL

* src/process.c (wait_reading_process_output): Don't retry reading
from an fd after an unknown error (bug#6074).

1 files changed, 3 insertions, 1 deletions

diff --git a/src/process.c b/src/process.c
index 3aa105ae342..53f4a1d8530 100644
--- a/src/process.c
+++ b/src/process.c
@@ -5413,14 +5413,16 @@ wait_reading_process_output (intmax_t time_limit, int nsecs, int read_kbd,
           /* If data can be read from the process, do so until exhausted.  */
           if (wait_proc->infd >= 0)
             {
+              unsigned int count = 0;
               XSETPROCESS (proc, wait_proc);
 
               while (true)
                 {
                   int nread = read_process_output (proc, wait_proc->infd);
+                  rarely_quit (++count);
                   if (nread < 0)
                     {
-                      if (errno == EIO || would_block (errno))
+                      if (errno != EINTR)
                         break;
                     }
                   else