Reusable Method Code

Get User Confirmation

# User Confirmation:
# requires MSG-CONFIRM, assigns EXIT
#
echo -e -n '\n\e[1;31m $MSG-CONFIRM'
read -n 1 -p ' (y/n)?' RESP
echo -e '\e[0m'
case $RESP in
  y|Y)
    EXIT='0'
  n|N)
    EXIT='1'
  *)
    EXIT='2'
esac

Assign Variables from File

# assign configuration to variables
# config-file lines format: VAR-NAME=VAR-VALUE
# uses "printf -v VAR-NAME VAR-VALUE"
#
# requires FILE-CONFIG, assigns VAR-NAME, VAR-VALUE
if [ -s "$FILE-CONFIG" ]
then
  # read configuration into array
  SAVEIFS=$IFS
  IFS=$'\n'
  VARLIST=($(<"$FILE-CONFIG"))
  IFS=$SAVEIFS
  # assign array to named variables using printf -v
  for (( i=0; i<${#VARLIST[@]}; i++ ))
  do
    VAR-NAME=${VARLIST[i]%%=*}
    VAR-VALUE=${VARLIST[i]##*=}
    printf -v $VAR-NAME $VAR-VALUE
  done
fi

Ask to Escalate Privileges

if [[ $EUID -ne 0 ]]
then
  echo -e "\e[1;31m try again using sudo \e[0m"
  exit 1
fi

Change Configuration Entry

# change entry in text file
# requires FILE-PATH, SEARCH, REPLACE
#
if [[ -z "$(grep 'vm.mmap_min_addr' /etc/modules)" ]] ; then
   echo -e /n "vm.mmap_min_addr=0" >> /etc/modules ;
else
   sed -i '/vm.mmap_min_addr/c\vn.mmap_min_addr=0' ~/etc/modules ;
fi

Here Document

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