sorting and reversing lines of a file

Tony L. Hansen hansen at pegasus.ATT.COM
Sat Feb 11 12:12:50 AEST 1989


>>(1) reverse the order of lines in a file
>>    but leave the lines themselves intact.
>>    The Unix utility does just the opposite of this.

This sounds like a job for "tac" which has been posted at least a couple of
times to the net. Here's the man page.

    NAME
	tac - concatenate and print files in reverse

    SYNOPSIS
	tac file ...

    DESCRIPTION
	Tac reads each file in sequence and writes it on the standard
	output with the lines in reverse order. Thus:

		tac file

	prints the file in reverse, and:

		tac file1 file2 >file3

	concatenates the first two files, reversed, and places the result
	on the third.

		tac file | tac

	will reproduce the contents of the file. If no input file is given,
	or if the argument - is encountered, tac reads from the standard
	input.

    WARNING
	Command formats such as

		tac file1 file2 >file1

	will cause the original data in file1 to be lost, therefore, take
	care when using shell special characters.

    SEE ALSO
	cat(1).

					Tony Hansen
				att!pegasus!hansen, attmail!tony



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