AndrewMcHorney wrote:
Hi
Hello,
I appreciate the assistance from a previous email message on writing
functions in Perl. The issue right now is that I am passing an array, a
number and a string to the function but it does not appear to be passed
successfully. I am sure the error is quite simple. The function in
question is build_string. Any assistance would be greatly appreciated.
#! /bin/perl
use warnings;
use strict;
sub array_eq
{
my $aref = shift;
my $bref = shift;
if (@$aref != @$bref)
{
return 0
}
# compare size
for my $i (0..$#$aref)
{
#
# compare values
#
return 0 unless $$aref[$i] eq $$bref[$i];
}
return 1;
}
sub build_string
{
my $array = shift;
my $start_index = shift;
my $separator = shift;
You do not use this variable anywhere in this subroutine.
$array_size = @$array;
$built_string = "";
print "passed in array".$array[$start_index]."\n";
$array contains a reference to an array so you have to dereference it to
access an element:
print "passed in array" . $array->[ $start_index ] . "\n";
while ($start_index < $array_size +1)
You are trying to access an element of the array past the end of the array.
{
$built_string = $built_string.$array[$start_index];
$start_index = $start_index + 1;
}
return $built_string;
}
That subroutine could be simply written as:
sub build_string {
my ( $array, $start_index ) = @_;
return join '', @{ $array }[ $start_index .. $#$array ];
}
#
# Read the list of drives to go through
#
$num_args = @ARGV;
$DRIVE_LIST_FILE = "DriveList.txt";
open DRIVE_LIST_FILE, $DRIVE_LIST_FILE or die "Cannot open drive list file\n";
You should include the $! or $^E variable in the error message so you
know *why* open failed and probably also the file name so you know which
file failed to open.
@DriveList = (<DRIVE_LIST_FILE>);
The parentheses are superfluous.
$DriveListSize = scalar(@DriveList);
The use of scalar() is superfluous.
close DRIVE_LIST_FILE;
$DriveIndex = 0;
$FileCount = 0;
$DirectoryCount = 0;
#
# Create the duplicate file list file
#
($Seconds,$Minutes,$Hours,$Day,$Month,$Year) = (localtime)[0,1,2,3,4,5];
$Year = $Year + 1900;
Or simply:
my ( $Seconds, $Minutes, $Hours, $Day, $Month, $Year ) = localtime;
$Date = sprintf("%02d",$Month)."-";
$Date = $Date.sprintf("%02d",$Day)."-";
$Date = $Date.sprintf("%04d",$Year)."-";
$Date = $Date.sprintf("%02d",$Hours)."_";
$Date = $Date.sprintf("%02d",$Minutes)."_";
$Date = $Date.sprintf("%02d",$Seconds);
Or simply:
my $Date = sprintf '%02d-%02d-%04d-%02d_%02d_%02d', $Month + 1, $Day,
$Year + 1900, $Hours, $Minutes, $Seconds;
$DuplicateFileName = "Duplicate_File_List_".$Date;
#print $DuplicateFileName."\n";
$OpenStatus = 1;
open DUPLICATE_FILE_NAME, ">".$DuplicateFileName or $OpenStatus = 0;
if ($OpenStatus == 0)
{
print "$!";
print " ";
die "Unable to open duplicate file name file\n";
The output from print() is normally buffered and the output from die()
is unbuffered so the third line will display immediately and the first
two lines will display when the buffer is full or flushed.
}
#
# Create the open failed file list file
#
$OpenFailedFileName = "Open_Failed_File_List_".$Date;
#print $OpenFailedFileName."\n";
open OPEN_FAILED_FILE_NAME, ">".$OpenFailedFileName or die "Unable to open open
failed file name file\n";
You should include the $! or $^E variable in the error message so you
know *why* open failed and probably also the file name so you know which
file failed to open.
#
# Loop through each drive to get a list of files
#
while ($DriveIndex < $DriveListSize)
{
$CurrentDrive = @DriveList[$DriveIndex];
That should be:
$CurrentDrive = $DriveList[ $DriveIndex ];
[ *SNIP* ]
John
--
Those people who think they know everything are a great
annoyance to those of us who do. -- Isaac Asimov
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