скрипт отключения 3g модема не работает, почему?
#!/bin/sh
killall pppd
sleep 3
cat /dev/ttyUSB0 &
x=$!
kill $x
sleep 3
exec /usr/sbin/chat -V -s -S \
ABORT "BUSY" \
ABORT "ERROR" \
ABORT "NO DIALTONE" \
SAY "\nSending break to the modem\n" \
"" "\K" \
"" "+++ATH" \
SAY "\nPDP context detached\n" \
"" "AT+CFUN=1,1" \
"" "ATZ" \
SAY "OK"
exit
linux-bst0:~ # killall pppd
pppd: no process found
linux-bst0:~ # sleep 3
linux-bst0:~ #
linux-bst0:~ # cat /dev/ttyUSB0 &
[1] 12469
linux-bst0:~ # x=$!
linux-bst0:~ # kill $x
linux-bst0:~ # sleep 3
[1]+ Terminated cat /dev/ttyUSB0
linux-bst0:~ #
linux-bst0:~ # exec /usr/sbin/chat -V -s -S \
> ABORT"BUSY"\
> ABORT"ERROR"\
> ABORT"NO DIALTONE"\
> SAY"\nSending break to the modem\n"\
> \"\""\K"\
> \"\""+++ATH"\
> SAY"\nPDP context detached\n" \
> "" "AT+CFUN=1,1" \
> "" "ATZ" \
> SAY "OK"
exit