The goal for this Programming Praxis was to implement the Unix wc function. This one took me a couple days (I haven’t had a lot of time recently) to complete, but I finally finished it and this it works pretty good. It’s not a drop in replacement for wc, but it works – a programmers solution: by programmers, for programmers.

use Switch;

#print "arg num ". $#ARGV;
if ($#ARGV == -1) {
	usage();
}

@option;
@input;

#check first char of each argument
foreach $arg (@ARGV){
	if($arg =~ m/-.*/){
		@option = split //, $arg;
		#print "!".$arg."\n";
	}
	else{
		push(@input, $arg);
	}
}
#remove the "-" from the array
shift(@option);

foreach $input (@input){
	
	if(-e $input){
	#file exists, continue
		local( *FH ) ;
		open( FH, $input ) or die "sudden flaming death\n";
		$file = do { local( $/ ) ; <FH> };
		$fileSize = (-s $input);
		close(FH);
	}else{
		die("No such file or directory");
	}
	print "$input ";
	foreach $flag (@option){
		switch ($flag){
			
			case "c" {print "$fileSize "}
			case "m" {print length($file) . " "}
			case "l" {print $file =~ s/((^|\s)\S)/$1/g ." "}
			case "L" {print maxLineLength($input)." "}
			case "w" {print $file =~ s/(\n)/$1/g . " "}
			else {die ("invalid option -- $flag")}
		}
	}
	print "\n";
}

sub maxLineLength($input){
	my($thisInput) = @_;
	open(FH, $thisInput);
	$maxLine = 0;
	foreach $line (<FH>){
		if(length($line) > $maxLine){
			$maxLine = length($line);
		}
	}
	return $maxLine;
}

sub usage{

	print "Usage: wc [OPTION]... [FILE]...\n";
	print "  or:  wc [OPTION]... --files0-from=F\n";
	print "Print newline, word, and byte counts for each FILE, and a total line if\n";
	print "more than one FILE is specified.  With no FILE, or when FILE is -,\n";
	print "read standard input.\n";
	print "  -c            print the byte counts\n";
	print "  -m            print the character counts\n";
	print "  -l            print the newline counts\n";
	print "  -L, --max-line-length  print the length of the longest line\n";
	print "  -w, --words            print the word counts\n";
}