diff --git a/ueforth/esp32/template.ino b/ueforth/esp32/template.ino
index 6e7c50d..074444b 100644
--- a/ueforth/esp32/template.ino
+++ b/ueforth/esp32/template.ino
@@ -174,7 +174,9 @@
     n0 = (cell_t) lseek(fd, tos, SEEK_SET); n0 = n0 < 0 ? errno : 0) \
   X("RESIZE-FILE", RESIZE_FILE, cell_t fd = n0; DROP; n0 = ResizeFile(fd, tos)) \
   X("FILE-SIZE", FILE_SIZE, struct stat st; w = fstat(n0, &st); \
-    n0 = (cell_t) st.st_size; PUSH w < 0 ? errno : 0)
+    n0 = (cell_t) st.st_size; PUSH w < 0 ? errno : 0) \
+  X("NON-BLOCK", NON_BLOCK, n0 = fcntl(n0, F_SETFL, O_NONBLOCK); \
+    n0 = n0 < 0 ? errno : 0)
 
 #ifndef ENABLE_LEDC_SUPPORT
 # define OPTIONAL_LEDC_SUPPORT
diff --git a/ueforth/posix/httpd.fs b/ueforth/posix/httpd.fs
index fad3359..a2335ae 100644
--- a/ueforth/posix/httpd.fs
+++ b/ueforth/posix/httpd.fs
@@ -30,16 +30,20 @@ sockaddr httpd-port   sockaddr client   variable client-len
 
 : handleClient
   clientfd close-file drop
+  -1 to clientfd
   sockfd client client-len sockaccept
-  dup 0< if drop exit then to clientfd
+  dup 0< if drop 0 exit then
+  to clientfd
   chunk chunk-size 0 fill
   chunk chunk-size clientfd read-file throw to chunk-filled
+  -1
 ;
 
 : server ( port -- )
   httpd-port ->port!  ." Listening on port " httpd-port ->port@ . cr
   AF_INET SOCK_STREAM 0 socket to sockfd
   ( sockfd SOL_SOCKET SO_REUSEADDR 1 >r rp@ 4 setsockopt rdrop throw )
+  sockfd non-block throw
   sockfd httpd-port sizeof(sockaddr_in) bind throw
   sockfd max-connections listen throw
 ;
diff --git a/ueforth/posix/posix.fs b/ueforth/posix/posix.fs
index 706a703..5f08721 100644
--- a/ueforth/posix/posix.fs
+++ b/ueforth/posix/posix.fs
@@ -148,6 +148,11 @@ z" clock_gettime" 2 sysfunc clock_gettime
 8 constant CLOCK_REALTIME_ALARM
 9 constant CLOCK_BOOTTIME_ALARM
 
+( File control )
+z" fcntl" 3 sysfunc fcntl
+4 constant F_SETFL
+2048 constant FNDELAY ( 04000 )
+
 forth definitions posix
 
 ( Generic Files )
@@ -172,6 +177,9 @@ O_RDWR constant r/w
    dup 0 SEEK_END lseek r> swap >r
          SEEK_SET lseek drop r> d0<ior ;
 
+( Non-standard )
+: non-block ( fh -- ior ) F_SETFL FNDELAY fcntl ;
+
 ( Other Utils )
 : ms ( n -- ) 1000 * usleep drop ;
 : ms-ticks ( -- n )
diff --git a/ueforth/posix/sockets.fs b/ueforth/posix/sockets.fs
index 4b2619e..17435ce 100644
--- a/ueforth/posix/sockets.fs
+++ b/ueforth/posix/sockets.fs
@@ -36,4 +36,7 @@ z" setsockopt" 5 sysfunc setsockopt
 : ->port@ ( a -- n ) 2 + >r r@ c@ 256 * r> 1+ c@ + ;
 : ->port! ( n a --  ) 2 + >r dup 256 / r@ c! r> 1+ c! ;
 
+( Fixup return )
+: sockaccept sockaccept sign-extend ;
+
 forth definitions
diff --git a/ueforth/posix/telnetd.fs b/ueforth/posix/telnetd.fs
index e69cf00..b68b25c 100644
--- a/ueforth/posix/telnetd.fs
+++ b/ueforth/posix/telnetd.fs
@@ -32,13 +32,20 @@ defer broker
   ['] telnet-key is key
   ['] telnet-type is type quit ;
 
+: wait-for-connection
+  begin
+    sockfd client client-len sockaccept
+    dup 0 >= if exit else drop then
+  again
+;
+
 : broker-connection
   rp0 rp! sp0 sp!
   begin
     ['] default-key is key   ['] default-type is type
     -1 echo !
     ." Listening on port " telnet-port ->port@ . cr
-    sockfd client client-len sockaccept
+    wait-for-connection
     ." Connected: " dup . cr connection
   again ;
 ' broker-connection is broker
@@ -46,6 +53,7 @@ defer broker
 : server ( port -- )
   telnet-port ->port!
   AF_INET SOCK_STREAM 0 socket to sockfd
+  sockfd non-block throw
   sockfd telnet-port sizeof(sockaddr_in) bind throw
   sockfd 1 listen throw   broker ;
 
diff --git a/ueforth/posix/termios.fs b/ueforth/posix/termios.fs
index 5376a77..f4e42d7 100644
--- a/ueforth/posix/termios.fs
+++ b/ueforth/posix/termios.fs
@@ -18,12 +18,9 @@ vocabulary termios   termios definitions also posix
 
 z" tcgetattr" 2 sysfunc tcgetattr
 z" tcsetattr" 3 sysfunc tcsetattr
-z" fcntl" 3 sysfunc fcntl
 z" ioctl" 3 sysfunc ioctl
 
 ( Blocking )
-4 constant F_SETFL
-2048 constant FNDELAY
 : nodelay-mode   stdin F_SETFL FNDELAY fcntl throw ;
 : delay-mode   stdin F_SETFL 0 fcntl throw ;
 
diff --git a/ueforth/posix/web_interface.fs b/ueforth/posix/web_interface.fs
index b5f4574..97cf064 100644
--- a/ueforth/posix/web_interface.fs
+++ b/ueforth/posix/web_interface.fs
@@ -47,11 +47,11 @@ body {
 <body>
 <h2>ESP32forth v7</h2>
 Upload File: <input id="filepick" type="file" name="files[]"></input><br/>
-<button onclick="ask('hex')">hex</button>
-<button onclick="ask('decimal')">decimal</button>
-<button onclick="ask('words')">words</button>
-<button onclick="ask('low led pin')">LED OFF</button>
-<button onclick="ask('high led pin')">LED ON</button>
+<button onclick="ask('hex\n')">hex</button>
+<button onclick="ask('decimal\n')">decimal</button>
+<button onclick="ask('words\n')">words</button>
+<button onclick="ask('low led pin\n')">LED OFF</button>
+<button onclick="ask('high led pin\n')">LED ON</button>
 <br/>
 <textarea id="output" readonly></textarea>
 <input id="prompt" type="prompt"></input><br/>
@@ -73,8 +73,9 @@ function httpPost(url, data, callback) {
   r.open('POST', url);
   r.send(data);
 }
+setInterval(function() { ask(''); }, 300);
 function ask(cmd, callback) {
-  httpPost('/input', cmd + '\n', function(data) {
+  httpPost('/input', cmd, function(data) {
     if (data !== null) { output.value += data; }
     output.scrollTop = output.scrollHeight;  // Scroll to the bottom
     if (callback !== undefined) { callback(); }
@@ -83,7 +84,7 @@ function ask(cmd, callback) {
 prompt.onkeyup = function(event) {
   if (event.keyCode === 13) {
     event.preventDefault();
-    ask(prompt.value);
+    ask(prompt.value + '\n');
     prompt.value = '';
   }
 };
@@ -102,7 +103,7 @@ filepick.onchange = function(event) {
   }
 };
 window.onload = function() {
-  ask('');
+  ask('\n');
   prompt.focus();
 };
 </script>
@@ -130,10 +131,11 @@ create out-string out-size 1+ allot align
 : serve-key ( -- n ) input-stream stream>ch ;
 
 : handle1
-  handleClient
-  s" /" path str= if handle-index exit then
-  s" /input" path str= if handle-input exit then
-  notfound-response
+  handleClient if
+    s" /" path str= if handle-index exit then
+    s" /input" path str= if handle-input exit then
+    notfound-response
+  then
 ;
 
 : do-serve    begin handle1 pause again ;
@@ -141,8 +143,8 @@ create out-string out-size 1+ allot align
 
 : server ( port -- )
    server
-   ['] serve-type is type
    ['] serve-key is key
+   ['] serve-type is type
    webserver-task start-task
 ;