#!/bin/sh -u
#   $0    (no arguments)
# Purpose: Read two filenames.  Translate the first file to UPPER CASE
# and store into the second file.
#
# WARNING: Many of the comments in this file are "Instructor-Type"
#   comments and are *not* appropriate for real scripts.  Do not put
#   "Instructor-Type" comments into the scripts that you submit for marking.
#   I put them in my example files because I am teaching you how to
#   write scripts; do not submit my teaching comments back to me again.
# -IAN! idallen@ncf.ca

# Set the search path for the shell to be the standard places.
# Set the umask to be non-restrictive and friendly to others.
#
export PATH=/bin:/usr/bin
umask 022

# Prompt (always on standard error) for two file names.
# Read two names into shell variables $infile and $outfile.
#  - NOTE: no dollar signs are used in the "read" statement!
#
echo 1>&2 "Please enter an input file and output file name:"
read infile outfile

# Translate the input file as UPPER-CASE into the output file.
# The current umask determines the new permissions of the output file
# if it doesn't already exist.
# Always quote the use of variables to prevent the shell from expanding
# glob/wildcard characters inside them.
# Quote the two arguments to "tr" as well, just to be safe.
#
tr 'a-z' 'A-Z' <"$infile" >"$outfile"