Shell Programming and Scripting

#!/bin/bash
# Check for input file on command line.
ARGS=1
E_BADARGS=65
E_NOFILE=66

if [ $# -ne "$ARGS" ]  # Correct number of arguments passed to script or too complicated for something easy?
then
  echo "Usage: `basename $0` filename"
  exit $E_BADARGS
fi

if [ ! -f "$1" ]       # Check if file exists.
then
  echo "File \"$1\" does not exist."
  exit $E_NOFILE
fi


#so far i have it set to translate output by feeding tr back to itself. will this work?
#or is awk more effective. what about the use of | sort | uniq -c?

tr A-Z a-z | tr '[:space:]' Z | \
tr -cs '[:alpha:]' Z | tr -s '\173-\377' Z | tr Z ' '` 

# for or while loop?

> output.txt 


exit 0

tr -cd '[:space:][:alnum:]'

John Smith  555-5555  to 555-5555 Hello Jane Doe

while read line 

do echo "${line}"

 done < <(cat file.lst)

/tmp/file1.txt
/tmp/file with space.txt

cd <input_file_directory>
for file in `dir -d *` ; do
<exeFile with full path> "$file" <output_file_path/"$file".out>
done

#!/bin/bash

[[ BASH_VERSINFO -ge 4 ]] || {
    echo "Bash version 4.0 or newer is required by this script."
    exit 1
}

declare -A FLAGS=()

while read; do
    REPLY=${REPLY//[^[:print:]]}
    [[ -n ${FLAGS[$REPLY]} ]] && continue
    FLAGS[$REPLY]=.
    echo "$REPLY"
done

exit 0

tr -cd '[:print:]' input_file | sort -u

cat file.txt |while read line; do echo "${line}"; done >> output.txt

cat *.txt ...