Issue with sendmail

[Denys Vlasenko]

On Thu, Mar 15, 2012 at 11:05 AM, Javier Uria <javier.uria at vdi-e.es> wrote:
> I have built Busybox v1.19.4 with Buildroot for my target device and added
> the sendmail command.
>
> The problem is that I am not allowed to tell sendmail to stop getting data
> from stdin and finally send the email.
>
> I have tried in the following ways:
>
> 1. sendmail -f from at domain.com -S smtpserver.domain.com to at domain.com
>
> And then sendmail waits for data from stdin. I write anything and then try
> with Enter, Ctrl-D, Enter again, and so on, but it never stops waiting for
> more data.
>
> 2. sendmail -f from at domain.com -S smtpserver.domain.com to at domain.com <
> mail.txt
>
> Where mail.txt contains the body of the message to be sent. After this,
> sendmail still waits for data from stdin.

Can't reproduce.
Why do you think it waits *on stdin*? In my testing it does not.
Please post the strace of this sendmail invocation (use strace
options -s99 -tt).