generalParallel

#########################################################################
# File Name: parallel.sh
# Author: C.J. Liu
# Mail: samliu@hust.edu.cn
# Created Time: Tue 06 Dec 2016 04:39:49 PM CST
#########################################################################
#!/usr/bin/env bash

params=$#
scripts=$1

# Set default threads as 20
threads=${2:-20}

echo "Notice: Your did parallel in $threads threads."
echo ""

function usage {
	Description="Notice: The script aimed at running shell command in general parallel."
	Usage="Uage:	generalParallel shell_scripts.sh parallel_number(default:20)"
	ErrorNo="Error:	Number of arguments must be 1 or 2"
	ErrorScript="Error:	suffix of script file must be sh."
	if [ "$params" -lt 1 -o "$params" -gt 2 ]; then
		echo $ErrorNo
		echo $Description
		echo $Usage
		exit 1
	fi
	if [ "${scripts#*.}" != "sh" ]; then
		echo $ErrorScript
		echo $Description
		echo $Usage
		exit 1
	fi
	if [ $threads -gt 20 ]; then
		echo "Warnings: Your THREADS is $threads"
		echo "Warnings: Be careful! Your THREADS EXCEED 20!!!"
	fi


}

# Usage
usage

# Make fifo file
pipe="${HOME}/tmp/$$.fifo"
mkfifo $pipe
exec 6<>$pipe
rm -rf $pipe

[[ $threads -gt 20 ]] && echo "Warnings: Your THREADS is $threads" && echo "Warnings: Be careful! Your THREADS EXCEED 20!!!"

for (( i=0; i<$threads; i++ ))
do
	echo ""
done >&6

cat $scripts | while read cmd
do
	read -u6
	{
		cmd=${cmd%%&}
		echo "Notice - Your are running $cmd on the $HOSTNAME"
		eval $cmd
		echo "Success - $cmd was done!!! on the $HOSTNAME"
		echo "" >&6
	}&
done
wait
exec 6>&-

wait