Single-character substitution is usually easiest with tr: 

my ($filename, $newfile);
foreach $filename (readdir(DIR))
{
    ($newfile = $filename) =~ tr/ /./;
    rename($filename, $newfile);
}

[download]
As a bonus, this will replace every space with a period. (That is a bonus, right? ;-)

Also, you want to either chdir to the target directory, or prepend the directory name to the file names. When possible, I prefer chdir: 

chdir $dir or die "Can't chdir to $dir: $!\n";
opendir(DIR, '.') or die "Can't open '.': $!\n";

[download]

HTH

In reply to Re: How can I opendir, replace all files containing a space with .? by VSarkiss
in thread How can I opendir, replace all files containing a space with .? by nkpgmartin

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