find-suffixes

#!/bin/bash
#
# find-suffixes - Examing all files from . downwards finding
#                 their suffixes
#
# Copyright (C) 2017 Michael Davies <michael@the-davies.net>
#
# 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 2 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, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
# 02111-1307, USA.
#

# Use DEBUG from the environment, but ensure that we don't error if it's not
if [ -z "$DEBUG" ]; then
  DEBUG=0
fi

EXTS=(fred)

OIFS="$IFS"
IFS=$'\n'

# -prune is for all the MAC OS Xisms
for fullfile in $(find . -type f -and \( -name .DS_Store -prune -o -name .fseventsd \
    -prune -o -name .Spotlight-V100 -prune -o -name .Trashes -prune -o -print \) )
do

    filename=$(basename "$fullfile")
    extension="${filename##*.}"
    filename="${filename%.*}"

    if [ -z "$extension" ]; then
        continue
    fi

    # Check to see if suffix already exists, if not add it
    FOUND=0
    for existing in "${EXTS[@]}"
    do
        if [ "$existing" == "$extension" ] ; then
            FOUND=1
            break
        fi
    done

    if [ ${FOUND} -eq 0 ] ; then
        if [ ${DEBUG} -eq 1 ]; then
            echo "*** Found new extension $extension from file $fullfile"
        fi
        EXTS=("${EXTS[@]}" "$extension")
    fi

done
IFS="$OIFS"

EXTS=("${EXTS[@]:1}") #removed the 1st element
echo ${EXTS[@]}