Randomly run command

ran() { [ $((RANDOM%100)) -lt "$1" ] && shift && "$@"; }
Randomly decide whether to run a command, or fail. It's useful for testing purposes. . Usage: ran PERCENTAGE COMMAND [ARGS] Note: In this version the percentage is required. . This is like @sesom42 and @snipertyler's commands but in a USABLE form. . e.g. In your complicated shell script, put "ran 99" before a crucial component. Now, it will fail 1% of the time allowing you to test the failure code-path. ran 99 my_complex_program arg1 arg2
Sample Output
$ ran 50 echo hello; echo $?
hello
0
$ ran 50 echo hello; echo $?
1

5
By: flatcap
2015-07-16 13:32:45

2 Alternatives + Submit Alt

  • Command will succeed n% of the time. ran 75 will cause command to succeed 75% of the time. No argument will cause it to succeed 50% of the time. Show Sample Output


    0
    ran() { R=$((RANDOM%100)); if [ $R -gt "${1:-50}" ]; then echo FALSE; false; else echo TRUE; true; fi; }
    snipertyler · 2015-07-15 15:34:56 0
  • Command will succeed n% of the time. ran 75 will cause command to succeed 75% of the time. No argument will cause it to succeed 50% of the time. Show Sample Output


    0
    ran() { [ $((RANDOM%100)) -lt ${1:-50} ]; }
    sesom42 · 2015-07-16 00:06:25 0

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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