How can I create my own script?

There are two possibilities how to create a script.

1. You can create the script on your pc in some text editor and then copy it to router via FTP (SFTP). Be careful while you are using Windows system because routers are based on Linux system (EOL - End Of Line). Windows system uses LF+CR unlike Linux system which uses only LF at end of line (EOL). The script can be copied to root folder what is in flash memory or to /var/data folder which is in MRAM. This is good for testing purpose.

2. Second possibility is to create the script from "Startup Script" and it is technique what we recommend. There are exist two techniques that you can use for creating a script from script.

• you can use cat with A here document, see the example below

Startup Script

#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here.
 
cat > /var/scripts/smsan.sh << EOF
#!/bin/sh
 
PHONE=+420734875410
an1thrshold=500
an2thrshold=500
an1txt="Activation an1"
an2txt="Activation an2"
OLD1=0
OLD2=0
 
while true
do
 
 VAL1=\`/usr/bin/io get an1\`
 if [ \$VAL1 -gt \$an1thrshold ]; then
    POMVAL1=1
 else
    POMVAL1=0  
 fi
 if [ "\$POMVAL1" != "\$OLD1" ]; then
   [ "\$POMVAL1" = "1" ] && gsmsms \$PHONE "\$an1txt"
   OLD1=\$POMVAL1
 fi
 
 VAL2=\`/usr/bin/io get an2\`
 if [ \$VAL2 -gt \$an2thrshold ]; then
    POMVAL2=1
 else
    POMVAL2=0  
 fi
 if [ "\$POMVAL2" != "\$OLD2" ]; then
   [ "\$POMVAL2" = "1" ] && gsmsms \$PHONE "\$an2txt"
   OLD2=\$POMVAL2
 fi
 
 sleep 1
 
done
EOF

Then the script will be created in folder /var/scripts and named smsan.sh. It will look like script below.

The script /var/scripts/smsan.sh sends SMS when input an1 or an2 reachs defined threshold.

#!/bin/sh
 
PHONE=+420734875410
an1thrshold=500
an2thrshold=500
an1txt="Aktivace an1"
an2txt="Aktivace an2"
OLD1=0
OLD2=0
 
while true
do
 
 VAL1=`/usr/bin/io get an1`
 if [ $VAL1 -gt $an1thrshold ]; then
    POMVAL1=1
 else
    POMVAL1=0  
 fi
 if [ "$POMVAL1" != "$OLD1" ]; then
   [ "$POMVAL1" = "1" ] && gsmsms $PHONE "$an1txt"
   OLD1=$POMVAL1
 fi
 
 VAL2=`/usr/bin/io get an2`
 if [ $VAL2 -gt $an2thrshold ]; then
    POMVAL2=1
 else
    POMVAL2=0  
 fi
 if [ "$POMVAL2" != "$OLD2" ]; then
   [ "$POMVAL2" = "1" ] && gsmsms $PHONE "$an2txt"
   OLD2=$POMVAL2
 fi
 
 sleep 1
 
done
EOF

• or you can use echo for that, see below

Startup Script

#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here.
 
echo -en "#!/bin/sh" \
         "\nPHONE=123456789" \
         "\nMESSAGE=\"BIN0 is active\"" \
         "\nwhile true" \
         "\ndo" \
         "\n  /usr/bin/io get bin0" \
         "\n  VAL=\$?" \
         "\n  if [ \"\$VAL\" != \"\$OLD\" ]; then" \
         "\n    [ \"\$VAL\" = \"0\" ] && gsmsms \$PHONE \$MESSAGE" \
         "\n    OLD=\$VAL" \
         "\n  fi" \
         "\nsleep 1" \
         "\ndone" >> /var/scripts/my_test.sh

Then the script will be created in folder /var/scripts and named my_test.sh. It will look like script below.

The script /var/scripts/my_test.sh sends SMS when bin0 is active.

#!/bin/sh
PHONE=123456789
MESSAGE="BIN0 is active"
while true
do
  /usr/bin/io get bin0
  VAL=$?
  if [ "$VAL" != "$OLD" ]; then
    [ "$VAL" = "0" ] && gsmsms $PHONE $MESSAGE
    OLD=$VAL
  fi
sleep 1
done

3. Finally you need prepare the script for running and run it. You can start it via cron or from also Startup Script¹ or UP/Down Script². Example below shows starting the script directly from Startup Script.

Startup Script or Up/Down Script

#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here.
  
echo -en "#!/bin/sh" \
         .
         .
# Here is body of your script.
         .
         .
         "\ndone" >> /var/scripts/my_test.sh
 
chmod 777 /var/scripts/my_test.sh
sh /var/scripts/my_test.sh &

NOTE:

¹ If you create the script from Startup Script then it will be done after each start up router. This technique supports to save it in configuration file and is retained after re-flash the router. 

² E.g. once you use never ending loop in your script and then run the script from "Up Script" you must finish the script from "Down Script" otherwise the script will be run multiple times (with each start WAN).