From ebc19a60ff5d32750384f5a99a315d5533d62058 Mon Sep 17 00:00:00 2001
From: wangjianyu3 <wangjianyu3@xiaomi.com>
Date: Fri, 8 Nov 2024 16:45:19 +0800
Subject: [PATCH] nshlib/cmd_cat: Retry if nsh_read was interrupted by a signal

When read from stdio of child process through pipe, SIGCHLD received if child exits.

Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>
---
 nshlib/nsh_fscmds.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/nshlib/nsh_fscmds.c b/nshlib/nsh_fscmds.c
index bf23beabe1..88f76d1ee3 100644
--- a/nshlib/nsh_fscmds.c
+++ b/nshlib/nsh_fscmds.c
@@ -802,10 +802,19 @@ int cmd_cat(FAR struct nsh_vtbl_s *vtbl, int argc, FAR char **argv)
       while (true)
         {
           ret = nsh_read(vtbl, buf, BUFSIZ);
-          if (ret <= 0)
+          if (ret == 0)
             {
               break;
             }
+          else if (ret < 0)
+            {
+              if (errno == EINTR)
+                {
+                  continue;
+                }
+
+              break;
+            }
 
           nsh_write(vtbl, buf, ret);
         }