telnetd: can't create pty?

[Dirk Behme]

Denys Vlasenko wrote:
> On Tuesday 26 February 2008 14:45, Dirk Behme wrote:
> 
>>Using BusyBox v1.9.1 on ARM target I want to telnet from PC to target. 
>>Starting BusyBox telnetd on target as daemon and then connecting from 
>>PC I get
>>
>> > telnet 192.0.0.2
>>Trying 192.0.0.2...
>>Connected to 192.0.0.2.
>>Escape character is '^]'.
>>Connection closed by foreign host.
>>
>>on PC. Starting telnetd on target with -F I get
>>
>># telnetd -F
>>telnetd: can't create pty
>>
>>on target while PC tries to connect.
>>
>>Any hint what's wrong here?
>>
>>I used similiar configuration with some older BusyBox working quite 
>>well. Now I switched to recent BusyBox and did some kernel 
>>re-configuration.
>>
>>Most probably this is a FAQ, and most probably I missed anything while 
>>playing with configuration, but sorry, I can't see the obvious at the 
>>moment. Searched already BusyBox ML archive, but couldn't find 
>>anything similiar.
>>
>>Many thanks
>>
>>Dirk
>>
>>Btw: I have
>>
>># ll /dev/pty
>>/dev/ptyp0  /dev/ptyp6  /dev/ptypc  /dev/ptyq2  /dev/ptyq8  /dev/ptyqe
>>/dev/ptyp1  /dev/ptyp7  /dev/ptypd  /dev/ptyq3  /dev/ptyq9  /dev/ptyqf
>>/dev/ptyp2  /dev/ptyp8  /dev/ptype  /dev/ptyq4  /dev/ptyqa
>>/dev/ptyp3  /dev/ptyp9  /dev/ptypf  /dev/ptyq5  /dev/ptyqb
>>/dev/ptyp4  /dev/ptypa  /dev/ptyq0  /dev/ptyq6  /dev/ptyqc
>>/dev/ptyp5  /dev/ptypb  /dev/ptyq1  /dev/ptyq7  /dev/ptyqd
>>#
>>
>>on my target and kernel is configured with
>>
>>CONFIG_UNIX98_PTYS=y
>>CONFIG_LEGACY_PTYS=y
>>CONFIG_LEGACY_PTY_COUNT=256
> 
> 
> Your busybox is probably configured with FEATURE_DEVPTS=y.
> It requires POSIX pseudoterminals, not BSD. Do you have
> /dev/ptmx? 

Ah, this was the trick!

Many thanks!

Dirk

> Do you have /dev/pts mounted?
> 
> # mount | grep devpts
> none on /dev/pts type devpts (rw)
> 
> Fix this, or turn off FEATURE_DEVPTS for busybox.
> --
> vda
>