One other possibility you might want to consider is to implement an FTP (or TFTP) _server_, rather than a client, on your lwIP device; this allows for push updates if desired. The user can then (optionally) accept the new image for installation locally. Down side is that this is even trickier as far as piercing firewalls, since end users would need to allow external ftp access to the device in the field or use a local ftp client from behind the firewall to download the update to the lwIP device.
-----Original Message----- From: lwip-users [mailto:lwip-users-bounces+jim.pettinato=fmcti....@nongnu.org] On Behalf Of Sergio R. Caprile Sent: Monday, May 21, 2018 8:26 AM To: lwip-users@nongnu.org Subject: Re: [lwip-users] Download a file for firmware upgrade You can do whatever you want. The question is probably not what can you do but what do you have available to obtain what you need with lesser effort. There are FTP clients around, I've collaborated in one of them using the RAW API, search the list. FTP is sometimes tricky and can give you some headaches with firewalls (and/or admins). For HTTP you need a client. I wouldn't just GET and hope everything is fine unless I can manage both ends (that means: the server too) and guarantee there won't be other stuff than my file. A HTTP client can be quite complicated, but you just need to get one resource at a specific URI You can even have a proprietary protocol running over TCP or UDP. If your device will be sold and installed on corporate networks, you might raise some concern among the net admins, asking to have open holes in the firewall does not seem to be a good way to make friends. My bet is to go for the user to upload the file, leveraging your web server; but if you must go out and get it, then perhaps FTP is the easiest full client and HTTP is the simplest firewall piercing. I don't know if there are running clients around. Particularly for your API, which you don't say. (I'm intentionally not considering TFTP for going out because of the possible firewall issue, but if it is your network, there is a client already available) _______________________________________________ lwip-users mailing list lwip-users@nongnu.org https://urldefense.proofpoint.com/v2/url?u=https-3A__lists.nongnu.org_mailman_listinfo_lwip-2Dusers&d=DwICAg&c=r_B2dqKkHczsuXPCSs5DOw&r=Ff303RP2ju9wUSYL2P1cGBtEK1syDf_ObW5leLha8yo&m=jjKDeebeofzLWM681_xyPLTIThzG-yCWeqOY0iP60bQ&s=8gfOdSZx85KndNC1SLnLV6jnsOguG69x_OqWqEfi5IY&e= _______________________________________________ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users