boot.expect

# This is for use with minicom, but needs you to configure it to
# use expect as its "Script program" instead of runscript.  Try
# Ctrl+A O -> Filenames and paths -> D

fconfigure stderr -buffering  none
fconfigure stdout -buffering  none

proc waitprompt { } {
    expect {
      "BusyBox" { puts stderr  "DONE\r"; exit 0 }
      "READY" { puts stderr ";;; READY\r"; }
      timeout { puts stderr ";;; timed out waiting after $line\r" }
    }
}

proc sendline { line } {
     send "$line; echo \$ready \r"
     sleep 0.1
}

log_user 0
log_file -a -open stderr

set f [open "result/boot.scr"]

send "setenv ready REA\r"
sleep 0.1
send "setenv ready \${ready}DY\r"
sleep 0.1

set timeout 300
expect_before timeout abort
while {[gets $f line] >= 0} {
    puts stderr ";;; next line $line\r"
    puts stderr ";;; waiting for prompt\r"
    puts stderr ";;; sending\r"	
    sendline $line
    waitprompt
}

puts stderr "done\r\n"
close $f