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RANDOM(6)                    FreeBSD Games Manual                    RANDOM(6)

     random -- random lines from a file or random numbers

     random [-elrUuw] [-f filename] [denominator]

     Random has two distinct modes of operations.  The default is to read in
     lines from the standard input and randomly write them out to the standard
     output with a probability of 1 / denominator.  The default denominator
     for this mode of operation is 2, giving each line a 50/50 chance of being

     The second mode of operation is to read in a file from filename and ran-
     domize the contents of the file and send it back out to standard output.
     The contents can be randomized based off of newlines or based off of
     space characters as determined by isspace(3).  The default denominator
     for this mode of operation is 1, which gives each line a chance to be
     displayed, but in a random(3) order.

     The options are as follows:

     -e      If the -e option is specified, random does not read or write any-
             thing, and simply exits with a random exit value of 0 to
             denominator - 1, inclusive.

     -f filename
             The -f option is used to specify the filename to read from.
             Standard input is used if filename is set to `-'.

     -l      Randomize the input via newlines (the default).

     -r      The -r option guarantees that the output is unbuffered.

     -U      Tells random(6) that it is okay for it to reuse any given line or
             word when creating a randomized output.

     -u      Tells random(6) not to select the same line or word from a file
             more than once (the default).  This does not guarantee uniqueness
             if there are two of the same tokens from the input, but it does
             prevent selecting the same token more than once.

     -w      Randomize words separated by isspace(3) instead of newlines.

     random(3), fortune(6)

     The functionality to randomizing lines and words was added in 2003 by
     Sean Chittenden <>.

     No index is used when printing out tokens from the list which makes it
     rather slow for large files (10MB+).  For smaller files, however, it
     should still be quite fast and efficient.

FreeBSD 7.2                    February 8, 2003                    FreeBSD 7.2


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