coreutils: The sort command

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1 The ‘sort’ Command
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1 Next we’ll look at the ‘sort’ command.  This is one of the most powerful
1 commands on a Unix-style system; one that you will often find yourself
1 using when setting up fancy data plumbing.
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1    The ‘sort’ command reads and sorts each file named on the command
1 line.  It then merges the sorted data and writes it to standard output.
1 It will read standard input if no files are given on the command line
1 (thus making it into a filter).  The sort is based on the character
1 collating sequence or based on user-supplied ordering criteria.
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