I am working on a perl script as part of a book that I am reading through for fun. The first part of the script (which is all that I have completed so far) asks the user to name a file. It then coppies that file into a different file. When it is finished, it will search the file for a particular string and then replace that string with a new string. Anyways, when I run the program, before anything displays, I get a message in my terminal saying: "Name "main::READFILE" used only once: possible typo at ./findandreplace.plx line 17" Then the program creates the write file as exptected, but at the end of the program the file is blank. Also, my terminal gives me this message just before closing the program: "/home/rootless/Documents/test2.txt readline() on unopened filehandle at ./findandreplace.plx line 19." I am definitely opening a valid file with text. It is a plain text doccument that I created using cat > test.txt. Here is my code: 
#!/usr/bin/perl -w
use strict;
#This program asks for an input file, output file, a string, and a rep
+lacement string.  It then searches the input file for the string and 
+substitutes it with a phrase of the user's choice.

#Get fielnaem and strings
my ($infile, $outfile, $string, $rstring) ;
print "What file should I parse?\n" ;
chomp($infile = <STDIN>) ;
print "What expression should I look for?\n" ;
chomp($string = <STDIN>) ;
print "What should I replace that string with?\n" ;
chomp($rstring = <STDIN>) ;
print "What new file should I create with your replacement string?\n" 
+;
chomp($outfile = <STDIN>) ;

#Open the file, perform the substitutions, and create the new user nam
+ed file.
open (READFILE, "$infile") || die "Can not open your file for parsing:
+ $!" ;
open (WRITEFILE, ">$outfile") || die "Can not open new replacement fil
+e: $!" ;
while (<$infile>) {
    print WRITEFILE "$_" ;
}

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In reply to Newby question by Parmenides

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