#!/bin/sh
#
# function_sh - mind (mind@metalshell.com)
#
# Basic example on the function structures
#
#       [ http://www.metalshell.com ]

# creating a function in a shellscript is quite usefull, say you had alot of
# variables and you wanted to all of them back to 0 but don't want to manualy
# set them all to 0 everytime you need to, Well to make it simpiler you can
# make a function to do it and everytime you need your variables set to 0 you
# can just call the function..

# Below are some examples on how to do functions and why they are useful
# a few examples will include while loops to show how useful a function
# can be..

reset_variables()
{
        # increase i by 1
        i=`expr $i + 1`

        # set our variable y back to 0
        y=0
}

append_test()
{
        # append message.. to our string
        str="$1 message.."
}

# define y and i as an integer of 0
y=0
i=0

# define z as an integer of 10
z=10

# define t as an integer of 3
t=3

# start our first function structure
echo "--- \"reset_variables()\" example ---"

while [ $i -ne $t ]
do
        if [ $y -eq $z ]
        then
                # call reset_variables
                reset_variables
        fi

        # increase y by 1
        y=`expr $y + 1`

        if [ $i -ne $t ]
        then
                # print our current position
                echo "On number $y of $z - Times looped: $i of $t"
        fi

done

# start our second function structure
str="test"

echo
echo "--- \"append_test()\" example ---"

echo "Our string before append_test(): $str"

# call append_test with $str as our first argument
append_test $str

# display results..
echo "Our string after append_test(): $str"