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    +1.. As used in a script to assign output to a variable (w/o introducing a newline character and using zero padding for two places): x=$(awk -v min=$min_var -v max=$max_var 'BEGIN{srand(); printf("%.2d", int(min+rand()*(max-min+1)))}') Commented Apr 22, 2019 at 18:35
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    It's based on time? since I got the same value in 2 consecutive runs... Commented May 5, 2019 at 14:13
  • @ShaiAlon the current time is often used as the default seed value for srand() so usually, yes it's based on time, see Stéphane's sentence about that in his answer. You can get around that by changing the initial seed to a random number with awk -v min=5 -v max=10 -v seed="$(od -An -N4 -tu4 /dev/urandom)" 'BEGIN{srand(seed+0); print int(min+rand()*(max-min+1))}'. You could use $RANDOM instead of od ... /dev/random but then your seed value is in the relatively small range of 0 to 32767 and so you'll probably get noticeable repetitions in your output over time. Commented Aug 9, 2019 at 17:54
  • I've been burned too many times by various awk implementations' bad randomization to trust them, which is why my answer (also portable and pure posix) uses od on /dev/urandom Commented Mar 21, 2024 at 3:17