A bash shell utility for splitting large files into chunks of a defined size without splitting the file in the middle of lines

split.sh

#!/bin/bash

# -----------------------------------------
# (c) Copyright IBM Corp. 2015. All Rights Reserved. 
# Author:   Nathan Hernandez
# License:   Apache 2.0 ( http://www.apache.org/licenses/LICENSE-2.0 )
# 
# IBM cannot guarantee or imply reliability, serviceability, or function of this script file. The script code is provided "AS IS", without warranty of any kind. IBM shall not be liable for any damages arising out of your use of this code. 
# -----------------------------------------

USAGE="This script allows you to split a file into chunks of a defined size without\n"\
"splitting the file in the middle of lines.\n"\
"\n"\
"Usage: ./split.sh <size> <file>\n"\
"\tsize:\tThe desired size of each chunk written as a value followed by either \n"\
"\t\tM (megabytes) or G (gigabytes), e.g., 10M or 1G.\n"\
"\tfile:\tThe file you want to be split. The file must be either megabytes or \n"\
"\t\tgigabytes large.\n"

if [ $# == 0 ]; then
    echo -e "$USAGE"
    exit 1
fi

programRequired="split"

if [[ "$OSTYPE" == "linux-gnu" ]]; then
    programRequired="split"
elif [[ "$OSTYPE" == "freebsd"* ]]; then
    programRequired="gsplit" # Use gsplit instead of split on BSD.
elif [[ "$OSTYPE" == "darwin"* ]]; then
    programRequired="gsplit" # Use gsplit instead of split on Mac OSX.
else
    programRequired="split" # If all else fails, use split.
fi

command -v $programRequired >/dev/null 2>&1 || {
    echo >&2 "I require $programRequired, but it's not installed. Aborting."
    exit 1
}

chunkSize="$1"
file="$2"
echo "File: $file"
echo "Chunk size: $chunkSize"

fileSize=$(ls -lh $file | awk -F ' ' '{print $5}')
fileUnit="${fileSize: -1}"
fileSize="${fileSize%?}"

chunkUnit="${chunkSize: -1}"
chunkSize="${chunkSize%?}"

if [ "$fileUnit" != "M" ] && [ "$fileUnit" != "G" ]; then
    echo "Filesize needs to be in M (megabytes) or G (gigabytes). Aborting."
    exit 1
fi

if [ "$chunkUnit" != "M" ] && [ "$chunkUnit" != "G" ]; then
    echo "Chunk unit needs to be in M (megabytes) or G (gigabytes). Aborting."
    exit 1
fi

if [ "$fileUnit" == "G" ] && [ "$chunkUnit" == "M" ]; then
    fileSize=$((fileSize * 1000))
fi

chunks=$((fileSize / chunkSize))
echo "Creating $chunks chunks in tmp/$file/."

splitCommand="$programRequired --number=l/$chunks --numeric-suffixes $file chunk-"
# echo "$splitCommand"
eval $splitCommand

makeAndMove="mkdir -p tmp/$file/ && mv chunk-* tmp/$file/"
# echo "$makeAndMove"
eval $makeAndMove