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Splitting a file into parts

I have a file which I would like to split into certain number of parts. I
wrote a script using the split command. For example, if there are 19 lines
and I pass in a parameter of n=4, I would like the file to be split into
4 parts of 5,5,5,4 parts. I have looked into csplit but it doesn't seem to
be doing what I want it to do.
ASKER CERTIFIED SOLUTION
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amit_g
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ASKER

This does not work. I ran this running last night and it was still running this morning.
What do you mean that it is still running since last night? Is the file you are splitting huge? Even then whole night is way too long. In any case you should have first tested it on a smaller file.
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crovaxy

Use the 'dd' utility.

For a file with 100 bytes use:

dd if=/path/to/file_to_split of=/path/to/file_part1 count=25 bs=1
dd if=/path/to/file_to_split of=/path/to/file_part2 count=25 bs=1 skip=25
dd if=/path/to/file_to_split of=/path/to/file_part3 count=25 bs=1 skip=50
dd if=/path/to/file_to_split of=/path/to/file_part4 count=25 bs=1 skip=75

Check out the 'dd' man page for more information.
Ops, you want to split by lines... sorry!

Then you can use something like this:

filename=test_part2.txt
lines=4
total_lines=`cat $filename | wc -l`;
offset=4

while :; do
        if [ $offset -gt $total_lines ]; then
                echo "PART #"
                cat $filename | head -n $offset | tail -n $[$total_lines%$lines];
                break;
        else
                echo "PART #"
                cat $filename | head -n $offset | tail -n $lines;
                offset=$[$offset+$lines];
        fi
done
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ASKER

crovaxy, thank your for your response. I know that it can be done in a script but I was wondering if there was any way to do it using the split or csplit commands.
It can be. The command I posted is tested. You need to explain what did not work and how you used it.
the amit_g answer is correct. You can parse the file using that command. You're problem, probably, is that you're not passing the YourFileName argument to the split command. The YourFileName in the amit_g answer is just for the 'cat' command which will be parsed by 'wc' to achieve the total lines on the file... it is not the filename argument to the split command itself.

Eg:

n=4
split -l $((($(cat YourFileName | wc -l) + $n) / $n)) YouFileName