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Full Discussion: read file backwards
Top Forums Shell Programming and Scripting read file backwards Post 302137957 by bluemoon1 on Thursday 27th of September 2007 11:33:47 PM
Old 09-28-2007
read file backwards

Assume file1 contains a list of strings.
My first script is scanning the file and deals with the lines with a certain patern in it:

grep 'somepatern' file1 \
while read LINE ; do
doSomethingAboutIt
done

Now, I need a second script that deals with the same lines (& do something differently) but in the opposite order; the last line found in the file with that patern shuld be handled first.

Please help me. Thanks so much!!!

Last edited by bluemoon1; 09-28-2007 at 12:36 AM.. Reason: typo
 

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diff3(1)						      General Commands Manual							  diff3(1)

NAME
diff3 - 3-way differential file comparison SYNOPSIS
file1 file2 file3 DESCRIPTION
compares three versions of a file, and prints disagreeing ranges of text flagged with these codes: all three files differ file1 is different file2 is different file3 is different The type of change required to convert a given range of a given file to some other is indicated in one of these ways: Text is to be appended after line number n1 in file f, where f = or Text is to be changed in the range line n1 through line n2. If n1 = n2, the range can be abbreviated to n1. The original contents of the range follows immediately after a indication. When the contents of two files are identical, the contents of the lower-numbered file is suppressed. Produces a script for the editor that can be used to incorporate into file1 all changes between file2 and file3 (see ed(1)); i.e., the changes that normally would be flagged and Produces a script to incorporate only changes flagged Produces a script to incorporate only changes flagged Produces a script that will incorporate all changes between file2 and file3, but treat overlapping changes (that is, changes that would be flagged with in normal listing) differently. The overlapping lines in both files will be inserted by the edit script bracketed by and lines. Produces a script that will incorporate only changes flagged , but treat these changes in the manner of option. The following command applies the resulting script to file1. EXTERNAL INFLUENCES
International Code Set Support Single- and multi-byte character code sets are supported. WARNINGS
Text lines that consist of a single period defeat Files longer than 64K bytes do not work. FILES
SEE ALSO
diff(1). diff3(1)
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