ppp-on-dialer中的变量

ppp-on:
#!/bin/sh
#
# Script to initiate a ppp connection. This is the first part of the
# pair of scripts. This is not a secure pair of scripts as the codes
# are visible with the 'ps' command. However, it is simple.
#
# These are the parameters. Change as needed.
TELEPHONE="*99***1#"
ACCOUNT=
PASSWORD=
APN=CMNET
LOCAL_IP=0.0.0.0
REMOTE_IP=0.0.0.0
NETMASK=255.255.255.0
export TELEPHONE ACCOUNT PASSWORD APN
#
# This is the location of the script which dials the phone and logs
# in. Please use the absolute file name as the $PATH variable is not
# used on the connect option. (To do so on a 'root' account would be
# a security hole so don't ask.)
#
#DIALER_SCRIPT=/etc/ppp/ppp-dialer
DIALER_SCRIPT=/etc/ppp-on-dialer
#
# Initiate the connection
#
# I put most of the common options on this command. Please, don't
# forget the 'lock' option or some programs such as mgetty will not
# work. The asyncmap and escape will permit the PPP link to work with
# a telnet or rlogin connection. You are welcome to make any changes
# as desired. Don't use the 'defaultroute' option if you currently
# have a default route to an ethernet gateway.
#
echo $DIALER_SCRIPT
exec /sbin/pppd usehostname -detach   noipdefault debug lock modem crtscts 115200 \
/dev/ttyS1 usepeerdns novj asyncmap 20A0000 escape FF kdebug 0 $LOCAL_IPREMOTE_IP \
netmask $NETMASK nodefaultroute connect $DIALER_SCRIPT


ppp-on-dialer:
#!/bin/sh
#
# This is part 2 of the ppp-on script. It will perform the connection
# protocol for the desired connection.
#
exec chat -v \
TIMEOUT 3 \
ABORT '\nBUSY\r' \
ABORT '\nNO ANSWER\r' \
ABORT '\nRINGING\r\n\r\nRINGING\r' \
'' AT \
OK ATH \
OK ATE1 \
OK AT+CGATT=1 \
OK 'AT+CGDCONT=1,"IP","$APN"' \
OK ATD$TELEPHONE \
TIMEOUT 30
CONNECT ''

在ppp-on-dialer中使用OK 'AT+CGDCONT=1,"IP","$APN"'就没办法拨上CMNET，如果用OK 'AT+CGDCONT=1,"IP","CMNET"'就可以了，这是为什么呢，怎么解决呢？

在这个文件中ATD$TELEPHONE ，这里也是使用了变量的啊？　　　　　　

那个笑脸是什么符号啊？