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rand(1) [opendarwin man page]

RAND(1) 							      OpenSSL								   RAND(1)

NAME
rand - generate pseudo-random bytes SYNOPSIS
openssl rand [-out file] [-rand file(s)] [-base64] num DESCRIPTION
The rand command outputs num pseudo-random bytes after seeding the random number generator once. As in other openssl command line tools, PRNG seeding uses the file $HOME/.rnd or .rnd in addition to the files given in the -rand option. A new $HOME/.rnd or .rnd file will be written back if enough seeding was obtained from these sources. OPTIONS
-out file Write to file instead of standard output. -rand file(s) Use specified file or files or EGD socket (see RAND_egd(3)) for seeding the random number generator. Multiple files can be specified separated by a OS-dependent character. The separator is ; for MS-Windows, , for OpenVMS, and : for all others. -base64 Perform base64 encoding on the output. SEE ALSO
RAND_bytes(3) 0.9.7d 2003-11-20 RAND(1)

Check Out this Related Man Page

RAND(3) 								 1								   RAND(3)

rand - Generate a random integer

SYNOPSIS
int rand (void ) DESCRIPTION
int rand (int $min, int $max) If called without the optional $min, $max arguments rand(3) returns a pseudo-random integer between 0 and getrandmax(3). If you want a random number between 5 and 15 (inclusive), for example, use rand(5, 15). Caution This function does not generate cryptographically secure values, and should not be used for cryptographic purposes. If you need a cryptographically secure value, consider using random_int(3), random_bytes(3), or openssl_random_pseudo_bytes(3) instead. Note On some platforms (such as Windows), getrandmax(3) is only 32767. If you require a range larger than 32767, specifying $min and $max will allow you to create a range larger than this, or consider using mt_rand(3) instead. PARAMETERS
o $min - The lowest value to return (default: 0) o $max - The highest value to return (default: getrandmax(3)) RETURN VALUES
A pseudo random value between $min (or 0) and $max (or getrandmax(3), inclusive). EXAMPLES
Example #1 rand(3) example <?php echo rand() . " "; echo rand() . " "; echo rand(5, 15); ?> The above example will output something similar to: 7771 22264 11 SEE ALSO
srand(3), getrandmax(3), mt_rand(3), random_int(3), random_bytes(3), openssl_random_pseudo_bytes(3). PHP Documentation Group RAND(3)
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