Split File into chunks keeping complete lines in solaris - perl

Question

How can I split a file into 3 with equal (or almost equal) number of lines without breaking a line.
for example split a file of 25 lines into 3 files of 9,8 and 8 lines each.
I know of split -n l/3 but does not work on Solaris10.
Tried some stuff i got online but did not give desired result like:
!/usr/bin/ksh
fspec=~/input.list
num_files=3
total_lines=$(wc -l <${fspec})
((lines_per_file = (total_lines + num_files - 1) / num_files))
split -l ${lines_per_file} ${fspec} files.

Answer 1

Here is a generic solution for you in awk
awk '{a[NR]=$0} END {t=int (NR/s);r=((NR/s-t)*s);while (n<s) for (i=t*n+++1;i<=t*n;i++) print a[i] > "file"n;while (i++<=NR) print a[i-1] > "file"n}' s=3 infile
This splits the infile to s numbers of file. If you set s=3 you get file1 file2 file3
The data that does not divide up, ends up in last file.
Example
cat number
1 one
2 two
3 three
4 four
5 five
6 six
7 seven
8 eight
9 nine
10 ten
awk '{a[NR]=$0} END {t=int (NR/s);r=((NR/s-t)*s);while (n<s) for (i=t*n+++1;i<=t*n;i++) print a[i] > "file"n;while (i++<=NR) print a[i-1] > "file"n}' s=3 number
cat file1
1 one
2 two
3 three
cat file2
4 four
5 five
6 six
cat file3
7 seven
8 eight
9 nine
10 ten