get a random number in bash

echo $[RANDOM % 100] # range 0-99
use it to stagger cronjob or to get a random number increase the range by replacing 100 with your own max value
Sample Output
bash-4.1$ echo $[RANDOM % 100]
89

-2
By: anapsix
2013-05-25 19:02:00

These Might Interest You

  • Unlike other alternatives, this command only relies on bash builtins and should also work on windows platforms with the bash executable. Sparseness corresponds to the number 128 and can be adjusted. To print all possible digits instead of only 0 and 1 replace RANDOM%2 by RANDOM%10 or RANDOM%16 to add letters [A-F]. Show Sample Output


    0
    while true; do printf "\e[32m%X\e[0m" $((RANDOM%2)); for ((i=0; i<$((RANDOM%128)); i++)) do printf " "; done; done
    seb1245 · 2012-11-27 10:40:42 0
  • This mapping function is called RANDOM bash and enter a number between 1 and 100 Show Sample Output


    0
    imap <leader>r <C-r>=system('echo "$(($RANDOM % 100))"')<cr>
    voyeg3r · 2010-10-24 00:37:44 0
  • If X is 5, it will about a number between 1 and 5 inclusive. This works in bash and zsh. If you want between 0 and 4, remove the +1.


    28
    echo $[RANDOM%X+1]
    goodevilgenius · 2010-08-07 02:43:46 5
  • I like the fact the Patola's version uses only ones and zeros, but I also like the sparse output of the other versions. This one combines both of those features and eliminates some unnecessary cruft. You can vary the sparseness by changing "$(($RANDOM % 5))" to another number. The number in this term "$(($RANDOM % 4))" controls how frequently the numbers are output bold.


    21
    echo -e "\e[32m"; while :; do for i in {1..16}; do r="$(($RANDOM % 2))"; if [[ $(($RANDOM % 5)) == 1 ]]; then if [[ $(($RANDOM % 4)) == 1 ]]; then v+="\e[1m $r "; else v+="\e[2m $r "; fi; else v+=" "; fi; done; echo -e "$v"; v=""; done
    dennisw · 2009-09-27 15:30:38 2

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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