##
# \file

# To each interface a set of caller functions exist, that take an instance
# of an object and then in turn call the implementation for the class of
# this object. If there is none within the class it looks into its
# parent class and so forth.
#
# This is somewhat similar to late binding in real OOP languages, but
# by far not so elaborated. This is not a real object oriented language
# and will surely never ever provide all features these have.
#
# That said it has proven very usefull for me to orgnize code and prevent
# code duplication.
#
# \author	Georg Hopp
#
# \copyright
# Copyright © 2014 Georg Hopp
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

##
# get and export the locations of used programs and export them
# I assume that on every UNIX/shell variant at least [ is globally
# available. I will use it throughout all other scripts without
# checking for existence.
# I also assume through all scripts that eval is available.
#
[ -z "${WHICH}" ]    && WHICH="/usr/bin/which"
[ -z "${UNAME}" ]    && UNAME="$(${WHICH} uname 2>/dev/null)"
[ -z "${GREP}" ]     && GREP="$(${WHICH} grep 2>/dev/null)"
[ -z "${AWK}" ]      && AWK="$(${WHICH} awk 2>/dev/null)"
[ -z "${SED}" ]      && SED="$(${WHICH} sed 2>/dev/null)"
[ -z "${ECHO}" ]     && ECHO="$(${WHICH} echo 2>/dev/null)"
[ -z "${SORT}" ]     && SORT="$(${WHICH} sort 2>/dev/null)"
[ -z "${TR}" ]       && TR="$(${WHICH} tr 2>/dev/null)"
[ -z "${PRINTF}" ]   && PRINTF="$(${WHICH} printf 2>/dev/null)"
[ -z "${LOGGER}" ]   && LOGGER="$(${WHICH} logger 2>/dev/null)"
[ -z "${NPROC}" ]    && NPROC="$(${WHICH} nproc 2>/dev/null)"
[ -z "${LSCPU}" ]    && LSCPU="$(${WHICH} lscpu 2>/dev/null)"
[ -z "${SYSCTL}" ]   && SYSCTL="$(${WHICH} sysctl 2>/dev/null)"
[ -z "${IP}" ]       && IP="$(${WHICH} ip 2>/dev/null)"
[ -z "${IFCONFIG}" ] && IFCONFIG="$(${WHICH} ifconfig 2>/dev/null)"

export WHICH UNAME GREP AWK SED ECHO SORT TR PRINTF LOGGER NPROC LSCPU IP IFCONFIG

# vim: set ts=4 sw=4: