UNIX for Dummies Questions & Answers

Loop:
 head -n 5000 <infile >file1
 tail -n +5001 <infile >file2
 cp file2 infile

NAME
       split - split a file into pieces

SYNOPSIS
       split [OPTION] [INPUT [PREFIX]]

DESCRIPTION
       Output fixed-size pieces of INPUT to PREFIXaa, PREFIXab, ...; default
       size is 1000 lines, and default PREFIX is `x'.  With no INPUT, or when
       INPUT is -, read standard input.

#!/usr/bin/env bash

# @(#) s1	Demonstrate successive slices of file.

FILE=${1-data1}

n=$( wc -l < $FILE )
echo " Info: processing $n lines of $FILE"
for (( i=1,e=5,j=1 ; i<=$n ; i+=5,e+=5 ))
do
  echo " Pass $j"
  sed -n "$i,${e}p" $FILE 
  # Pipe into process here or write file and process.
  (( j++ ))
done

% ./s1
 Info: processing 16 lines of data1
 Pass 1
1
2
3
4
5
 Pass 2
6
7
8
9
10
 Pass 3
11
12
13
14
15
 Pass 4
16