Bash script indenting command line

Question

Hi I have used the following script, which after it has run and exited, causes my command line to display no text when typing, and after each carriage return instead of starting a new line like

root@alix:~# 

root@alix:~# 

I get

root@alix:~# root@alix:~# root@alix:~# root@alix:~#  etc

When using ctrl c I get

root@alix:~# 
            root@alix:~# 
                        root@alix:~#  etc

Here is the script:

#!/bin/bash

###
### Run command for given number of seconds then kill it
###

read -p "How long should I run for? ==> " count_secs
echo "Time specified: " $count_secs

if [ $count_secs -gt 0 ]
then
   ###
   ### number of seconds greater than zero
   ###

   watch -n 0.5 'iw dev wlan0 station dump | grep "signal avg" >> processmonitor.log' >>/dev/null & 

   ###
   ### assume that the PID of the command is $$
   ###
   my_PID=$!
   sleep $count_secs
   kill -15 $my_PID
fi

Thanks.

Answer 1

You can use the following code without the need to kill any process, after the end of the specified time (secs) it will exit.

#!/bin/bash
###
### Run command for given number of seconds then kill it
###
read -p "How long should I run for? ==> " count_secs
echo "Time specified: " $count_secs
# $SECONDS is a shell variable
# we can use it in conjuction with
# our user input 
while [ "$SECONDS" -le "$count_secs" ]
do
  # execute any commands here (put your code bellow and remove echo commands)
  echo `date +%r`
  echo "i am doing my work now"
  # sleep (in secs) before the next execution
  sleep 1
done
# when the count_secs elapses exit
exit 0