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I'm looking way to make bash script that greps output of command and place strings into array and be able to randomly select 1 string from the array for example every minute and place it as variable, time for randomly selecting needs to be configurable.

Command output:
string
string2
string3

Place of all these strings into array and randomly select one of them and place it as variable

desired result:
strings -> array <- randomly selecting from array every 1 minute and placing string selected as variable for further use 
  • 1
    This is crying out for some example input together with corresponding desired output. – steve May 31 at 14:36
  • Selecting randomly every for example 1 minute, so this 1 minute is the time – niqo May 31 at 14:37
  • randomly selecting happens every minute so next minute random string is selected again, from the array where those string above are stored – niqo May 31 at 14:38
  • capture all at once – niqo May 31 at 14:43
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In bash, you can use readarray with command substitution to capture newline-separated outputs into an array; for exmaple:

readarray -t outputs < <(seq 10)

Where I've used seq 10 to produce some output. This results in:

$ declare -p outputs
declare -a outputs='([0]="1" [1]="2" [2]="3" [3]="4" [4]="5" [5]="6" [6]="7" [7]="8" [8]="9" [9]="10")'

To pseudorandomly select one of those elements every minute:

while :
do
  element=$(( RANDOM % ${#outputs[@]} ))
  var=${outputs[$element]}
  sleep 60
done

Noting that bash arrays start at index zero, the $(( )) arithemtic says to use the value of $RANDOM modulo the number of elements in the outputs array.

  • Nice and simple solution, thanks! – niqo May 31 at 16:49

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