UNIX for Advanced & Expert Users

jot -s" " 7200 1 7200 | ./rand.php

$ cat rand.php
#!/usr/bin/php
<?php
  $file = fopen( 'php://stdin', 'r' );
  $numarr = explode( " ", fgets( $file ) );
  srand();
  $nums = array_rand( $numarr, 1440 );
  echo implode( " ", $nums );
  fclose( $file );
?>

$ jot -s" " 7200 1 7200 | ./rand.php | wc -w
    1440

sort --random-sort inputfile | head -n 1440

awk 'BEGIN {srand(); } { A[NR-1]=$0; E++ }
        END { while(E>0) { print A[N=int(rand()*E)] A[N]=A[--E]; }' input > output