Hello Perl experts,
I am pretty new to Perl and having a memory problem with my code. I have narrowed it down to the following section of code which always seems to generate the out of memory error when running.(when the number of files are large).
                opendir (TXT, "$processedDirPath") or die "Cannot open
+ $processedDirPath directory $!\n";
                while ( (my $matchingFiles = readdir(TXT)) ) {
                    if ( $matchingFiles =~ /\.rtsd001$/ ) {
                        my @fileContents;
                        my $UNMODIFIED;
                        my $MODIFIED;
                        open(UNMODIFIED, "<$processedDirPath/$matching
+Files") or die "Cannot open $UNMODIFIED for reading $!\n";
                        open(MODIFIED, ">$processedDirPath/$matchingFi
+les.old") or die "Cannot open $MODIFIED for writing $!\n";
                        while (<UNMODIFIED>) {
                            /STRUC20/ and @fileContents=(), next or pu
+sh @fileContents, $_; # All files that end in rtsd001 will need to be
+ modified.
                        }
                        print MODIFIED @fileContents;
                        close(UNMODIFIED);
                        close(MODIFIED);
                        system( "/bin/mv", "$processedDirPath/$matchin
+gFiles.old", "$processedDirPath/$matchingFiles" ) == 0 or warn "Move 
+command filed $!\n";;
                    }
                }
                closedir TXT;

[download]

Now a little background. I want to process all files in a directory which is held by $processedDirPath variable and only work with files that end with "rtsd001".

I have also tried saving the readdir to an @array then grepping for the file extensions I want and doing a while loop against that.

What is the MOST memory efficient/best way to read files in a directory then modify each file found (Script will have to rewrite all files to remove lines before the STRUC20 line.)

The directory which I am running readdir against contains about 6-10 thousand files each about <1k - 40k> in size.

So, working with this large number of files what would be the best way to do this?
Thanks for the help in advance.

In reply to Readdir against large number of files by learningperl01

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