continuously print string as if being entered from the keyboard

cycle(){ while :;do((i++));echo -n "${3:$(($i%${#3})):1}";sleep .$(($RANDOM%$2+$1));done;}
Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption. cycle 1 3 $(openssl rand 100 | xxd -p) Fans of "The Shining" might get a kick out of this: cycle 1 4 ' All work and no play makes Jack a dull boy.'

2
2010-10-08 23:45:40

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What Others Think

Hello ! Please, can somebody explain to me how does this expression "${3:$(($i%${#3})):1}" work ?
JisSey · 360 weeks and 5 days ago
ok I got it now ;) {array:position:number of element to get} array=3 is a substitution for $3 (the 3rd parameter) when using the function call i%array_length is a loop cylcling between the vallues 0,1,2,3...,(array_length - 1) I have improved a bit the function by initializing the iterative variable so the printing can start from the first letter of the sentence => cycle(){i=$((${#3}-1));while :;do((i++));echo -n "${3:$(($i%${#3})):1}";sleep .$(($RANDOM%$2+$1));done;}
JisSey · 360 weeks and 4 days ago

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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