Renaming Files with Perl

[mustaine737]

I have 2 files on disk - oldfilename1.bak and oldfilename2.bak

My goal is to rename oldfilename1.bak to newfilename1.bak, oldfilename2.bak to newfilename2.bak

The old file names are held in a text file called - old.txt, contents ( one on each line) :
oldfilename1
oldfilename2

The new file names are held in a text file called - new.txt, contents (one on each line) :
newfilename1
newfilename2

I'm using this script, but it doesn't work. I think it is because there's a new line when I call the value from the array, can someone please give me any pointers? When I print the array, it looks okay.

*******

#!/usr/bin/perl

open (old,"old.txt") || die ("There was an error opening file: $!");
@oldnames = <old>;
close (old);

open (new,"new.txt") || die ("There was an error opening file: $!");
@newnames = <new> ;
close (new);

for $i (0 .. $#oldnames)
{
$a = "$oldnames[$i]";
$b = "$newnames[$i]";
rename("$a.bak","$b.bak");
}

*************

Thank you, very much.

 

[spookie]

mustaine737,
Yes, you are right. The problem is because of new line characted at the end of array element.
Remove it using chomp and it should be fine. Also try avoiding $a and $b names for varaibles as they are used for some special purpose.

for $i (0 .. $#oldnames)
{
$old = "$oldnames[$i]";
$new = "$newnames[$i]";
chomp($old);
chomp($new);
rename("$old.bak","$new.bak");
}

--------------------------------------------------------------------------
I never set a goal because u never know whats going to happen tommorow.

 

[3inen]

does this help. it reads old.txt file line by line and prints them to new.txt file.

#!/usr/bin/perl -w
open(FILER1, "old.txt") || die "couldn't open the file\n";
open(FILEW1, ">new.txt") || die "couldn't create the file\n";
while(!eof(FILER1)){
my $line=<FILER1>;
$line=~s/oldfilename/newfilename/;
print FILEW1 "$line";
}

 

[stevexff]

Having the data in two separate files is a bit risky - the files have to be kept in sync and one missing line could screw up all your renames. It would be safer to have a single file with pairs of filenames on each line...

Steve

[small]"Every program can be reduced by one instruction, and every program has at least one bug. Therefore, any program can be reduced to one instruction which doesn't work." (Object:erlDesignPatterns)[/small]

 

[ishnid]

Steve's got a point. It would be a good idea to at least check to make sure you have the same number of entries in each list.

 

[mustaine737]

All,

Thank you very much for your replies

I chomped the array and also added some logic to ensure that the file names are in sync.