I am passing this along so it might be somwhere searchable if anyone has
the same problem,

Basically my PICO Ws were not reconnecting to the Wifi after loss of
Wifi access point.

This, however seems to work

int main()
{
int ret;
struct tcp_pcb *connection;
char buf[2048];
stdio_init_all();
initialise_adc();
if (cyw43_arch_init_with_country(CYW43_COUNTRY_UK))
{
printf("Wi-Fi init failed");
return -1;
}
cyw43_arch_enable_sta_mode();
set_hostname(hostname);
sleep_ms(20);
printf("THERMOMETER FOR %s\n",hostname);
while (TRUE)
{
// *check wifi is up and connect/reconnect as necessary*..
while((cyw43_tcpip_link_status(&cyw43_state,CYW43_ITF_STA)) !=
CYW43_LINK_UP)
cyw43_arch_wifi_connect_timeout_ms(ssid, password,
CYW43_AUTH_WPA2_AES_PSK, 20000);
// do your stuff here...
sleep_ms(6000);
// rinse and repeat..
}
}

The key issue is that
cyw43_tcpip_link_status(&cyw43_state,CYW43_ITF_STA); will not return
CYW43_LINK_UP until *everything* is sorted out including DHCP assignment
of an IP address...

Fingers crossed this is now reasonably bullet proof.

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the right place whilst your head is in the clouds and your hand is in
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