tcp server with tftp

tcp server with tftp

[Yonkee, Nathan Paul]

Hello all, I am writing some custom uboot to run a tcp server to communicate with our lab computer. I would like to be able to do a tftp file transfer while the server is connected, but when I try I get error -13. I wrote a custom tcp server with lwip and I am using tftp_loop() to do the tftp transfer.

Re: tcp server with tftp

[Nathaniel Hourt]

On 2025-11-19 17:16, Yonkee, Nathan Paul wrote:
> Hello all, I am writing some custom uboot to run a tcp server to 
> communicate with our lab computer. I would like to be able to do a tftp 
> file transfer while the server is connected, but when I try I get error 
> -13. I wrote a custom tcp server with lwip and I am using tftp_loop() 
> to do the tftp transfer.

TFTP is usually a UDP-based protocol... Are you sure you mean to be 
using TCP with it?

If you're just looking to send a file to your device with u-boot, have 
you looked at the wget command? 
https://docs.u-boot.org/en/latest/usage/cmd/wget.html Or are you trying 
to send a file from u-boot to your lab computer?

—
Nathaniel

RE: [EXTERNAL] Re: tcp server with tftp

[Yonkee, Nathan Paul]

Thanks for the response. I am sending files from the pc to uboot. I tried wget and still get connection error -13 from lwip. It's coming from the function bound by tcp_err.

Nathan Yonkee
Sandia National Laboratories
Department 5324, NPC Motion Systems
npyonke@sandia.gov
505-844-7031

-----Original Message-----
From: U-Boot <u-boot-bounces@lists.denx.de> On Behalf Of Nathaniel Hourt
Sent: Wednesday, November 19, 2025 10:55 PM
To: u-boot@lists.denx.de
Subject: [EXTERNAL] Re: tcp server with tftp

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On 2025-11-19 17:16, Yonkee, Nathan Paul wrote:
> Hello all, I am writing some custom uboot to run a tcp server to
> communicate with our lab computer. I would like to be able to do a
> tftp file transfer while the server is connected, but when I try I get
> error -13. I wrote a custom tcp server with lwip and I am using
> tftp_loop() to do the tftp transfer.

TFTP is usually a UDP-based protocol... Are you sure you mean to be using TCP with it?

If you're just looking to send a file to your device with u-boot, have you looked at the wget command?
https://docs.u-boot.org/en/latest/usage/cmd/wget.html Or are you trying to send a file from u-boot to your lab computer?

-
Nathaniel