Question

The program I’m writing is suppose to open two directories and read through the files in them to compare the contents of those files. Then the functions that have changed in the files should be printed to a file. This program will mainly be checking .cpp files and .h files.

Currently I am trying to go through the directory and open the current file I am at to print the functions that have changed. However, I keep getting an error that states that the file is not a file and can’t be opened.

Here is part of my current code that I am using

use strict;
use warnings;
use diagnostics -verbose;
use File::Compare;
use Text::Diff;

my $newDir = 'C:\Users\kkahla\Documents\Perl\TestFiles2';
my $oldDir = 'C:\Users\kkahla\Documents\Perl\TestFiles';

chomp $newDir;
$newDir =~ s#/$##;
chomp $oldDir;
$oldDir =~ s#/$##;

# Checks to make sure they are directories
unless(-d $newDir or -d $oldDir) {
    print STDERR "Invalid directory path for one of the directories";
    exit(0);
}

# Makes a directory for the outputs to go to unless one already exists
mkdir "Outputs", 0777 unless -d "Outputs";

# opens output file
open (OUTPUTFILE, ">Outputs\\diffDirectoriesOutput.txt");
print OUTPUTFILE "Output statistics for comparing two directories\n\n";

# opens both directories
opendir newDir, $newDir;
my @allNewFiles = grep { $_ ne '.' and $_ ne '..'} readdir newDir;
closedir newDir;

opendir oldDir, $oldDir;
my @allOldFiles = grep { $_ ne '.' and $_ ne '..'} readdir oldDir;
closedir oldDir

Here is where I want to open the files to read through them:

elsif((File::Compare::compare("$newDir/$_", "$oldDir/$_") == 1)) {
    print OUTPUTFILE "File: $_ has been update. Please check marked functions for differences\n\n";
    diff "$newDir/$_", "$oldDir/$_", { STYLE => "Table" , OUTPUT => \*OUTPUTFILE};
    #Here is where I want to open the file but when I try it throws an error
    #Here are the two opens I have tried:
    open (FILE, "<$newDir/$_") or die "Can't open file"; #first attempt
    open (FILE, "<$_") or die "Can't open file"; #second attempt to see if it worked
}

I tried adding the flags

my @allNewFiles = grep { $_ ne '.' and $_ ne '..' && -e $_} readdir newDir;
my @allNewFiles = grep { $_ ne '.' and $_ ne '..' && -f $_} readdir newDir;

But that would simply remove all files that weren’t .pl file extensions. I tested that on some simple directories I have that have two copies of .txt, .cpp, .h, .c, .py, and .pl file extensions and it would only show that the .pl files were files.

I am new to perl and any help would be appreciated.

Answer 1

-f is returning undef with $! set to “No such file or directory” because you are passing a file name to -f instead of a path to the file.

Change

-f $_

to

-f "$newDir/$_"