From 8e0892b2f234fcb0306ae8d68883add7443d1fd5 Mon Sep 17 00:00:00 2001
From: SPRESENSE <41312067+SPRESENSE@users.noreply.github.com>
Date: Thu, 19 Aug 2021 12:38:13 +0900
Subject: [PATCH] nshlib: Fix write buffer position in nsh cp command

The iobuffer for write buffer position need to be update if write
API cannot write data at once.
---
 nshlib/nsh_fscmds.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/nshlib/nsh_fscmds.c b/nshlib/nsh_fscmds.c
index a52be8020..42815d29c 100644
--- a/nshlib/nsh_fscmds.c
+++ b/nshlib/nsh_fscmds.c
@@ -587,10 +587,11 @@ int cmd_cp(FAR struct nsh_vtbl_s *vtbl, int argc, char **argv)
     {
       int nbytesread;
       int nbyteswritten;
+      char *iobuffer = vtbl->iobuffer;
 
       do
         {
-          nbytesread = read(rdfd, vtbl->iobuffer, IOBUFFERSIZE);
+          nbytesread = read(rdfd, iobuffer, IOBUFFERSIZE);
           if (nbytesread == 0)
             {
               /* End of file */
@@ -621,10 +622,11 @@ int cmd_cp(FAR struct nsh_vtbl_s *vtbl, int argc, char **argv)
 
       do
         {
-          nbyteswritten = write(wrfd, vtbl->iobuffer, nbytesread);
+          nbyteswritten = write(wrfd, iobuffer, nbytesread);
           if (nbyteswritten >= 0)
             {
               nbytesread -= nbyteswritten;
+              iobuffer += nbyteswritten;
             }
           else
             {