the control-d works from the command-line operation of scanimage

IIUC, hitting Ctrl-D doesn't send a Ctrl-D character, but closes the file:

$ cat > file
<press ^D>
$ cat file
$ _

[download]

This results in a file 0 bytes long. So, have you tried to close the filehandle instead of trying to send it a Ctrl-D?

--
David Serrano

In reply to Re: sending a control signal to a scanner by Hue-Bond
in thread sending a control signal to a scanner by zentara

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