How would I tell a bash script to start over from the top?

For example, in the below script startover starts back from the top:

##########################################################################
## CHECK TIME
##########################################################################
time=$(date +%k%M)

if [[ "$time" -ge 1800 ]] && [[ "$time" -le 2200 ]];then
echo "Not a good time to transcode video!" && exit 0
else
echo "Excellent time to transcode video!" && echo "Lets get started!"
fi
##########################################################################
## CHECK TIME
##########################################################################
startover

Also keeping in mind exit 0 should be able to stop the script.

Put it in a while loop. I'd also suggest you add a "sleep" so that you're not racing your machine's CPU as fast as it will go:

while true; do
    ##########################################################################
    ## CHECK TIME
    ##########################################################################
    time=$(date +%k%M)

    if [[ "$time" -ge 1800 ]] && [[ "$time" -le 2200 ]]; then
        echo "Not a good time to transcode video!" && exit 0
    else
        echo "Excellent time to transcode video!" && echo "Lets get started!"
    fi
    ##########################################################################
    ## CHECK TIME
    ##########################################################################
    for i in {1..5}; do
        echo $i
        sleep 1
    done
done

You could "recurse" using the following line:

exec bash "$0" "$@"

Since $0 is the path to the current script, this line starts the script without creating a new process, meaning you don't need to worry about too many restarts overflowing the process table on your machine.

DO NOT USE WHILE LOOP at the start of the script since the condition below will exit the script and break the loop.

echo "Not a good time to transcode video!" && exit 0

You can try trapping the exit signal so that when the script exits it restarts

##########################################################################
## CHECK TIME
############bash##############################################################
trap '<path to script> ' EXIT
time=$(date +%k%M)

if [[ "$time" -ge 1800 ]] && [[ "$time" -le 2200 ]];then
echo "Not a good time to transcode video!" && exit 0
sleep 1;
else
echo "Excellent time to transcode video!" && echo "Lets get started!"
sleep 1;
fi
##########################################################################
## CHECK TIME
##########################################################################
echo 1
echo 2
echo 3
echo 4
echo 5
startover

Note: I add a sleep of 1 second because this will give you the time to see message. trap the exit signal and re-running the script is acting like a while loop. I am also assuming that these codes are in a script.

How about enclosing the entire script in a while loop? For example,

while :
do
    script
done

You may want to add a condition to break out of the loop.

This is not good practice, but what you asked for.

Put this at the end of your script. "$( cd "$( dirname "$0" )" && pwd )/$(basename $0)"

来源：https://stackoverflow.com/questions/27219901/how-would-i-tell-a-bash-script-to-start-over-from-the-top

标签

Linux

bash

repeat