Re: Reversing A File

You can use tac if you are on a Unix-like system:

$ echo "one
> two
> three" > foo
$ cat foo
one
two
three
$ tac foo
three
two
one
[download]

--
Andreas

Comment on Re: Reversing A File Download Code

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Re^2: Reversing A File by tuxz0r (Pilgrim) on Dec 12, 2007 at 16:06 UTC
If you don't have `tac` on your system (which some of our AIX boxes don't), you can also use this short script, #!/bin/sh file=$1; i=1 max=`wc -l $file \| cut -d' ' -f1,1 ` while [ $i -le $max ]; do tail -$i $file \| head -1 i=$((i+1)) done [download] Call it much like `tac`, `$ ./reverse your.file > reverse.file` [download] It's not as fast as `tac` obviously, but if you don't have 'tac' and want to reverse a file it does work. --- s;;:<).>\|\;\;_>?\\^0<\|=!]=,\|{\$/.'>\|<?.\|/"&?=#!>%\$\|#/\$%{};;y;,'} -/:-@[-`{-};,'}`-{/" -;;s;;$_;see; Warning: Any code posted by tuxz0r is untested, unless otherwise stated, and is used at your own risk.	[reply] [d/l] [select]

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Re^2: Reversing A File
by tuxz0r (Pilgrim) on Dec 12, 2007 at 16:06 UTC

tac

#!/bin/sh

file=$1;
i=1
max=`wc -l $file | cut -d' ' -f1,1 `

while [ $i -le $max ];
do
        tail -$i $file | head -1
        i=$((i+1))
done
[download]

tac

$ ./reverse your.file > reverse.file
[download]

tac

---
s;;:<).>|\;\;_>?\\^0<|=!]=,|{\$/.'>|<?.|/"&?=#!>%\$|#/\$%{};;y;,'} -/:-@[-`{-};,'}`-{/" -;;s;;$_;see;
Warning: Any code posted by tuxz0r is untested, unless otherwise stated, and is used at your own risk.

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