Filter filenames by pattern - perl

Question

I need to search for files in a directory that begin with a particular pattern, say "abc". I also need to eliminate all the files in the result that end with ".xh". I am not sure how to go about doing it in Perl.
I have something like this:
opendir(MYDIR, $newpath);
my #files = grep(/abc\*.*/,readdir(MYDIR)); # DOES NOT WORK
I also need to eliminate all files from result that end with ".xh"
Thanks, Bi

Answer 1

try
#files = grep {!/\.xh$/} <$MYDIR/abc*>;
where MYDIR is a string containing the path of your directory.

Answer 2

opendir(MYDIR, $newpath); my #files = grep(/abc*.*/,readdir(MYDIR)); #DOES NOT WORK
You are confusing a regex pattern with a glob pattern.
#!/usr/bin/perl
use strict;
use warnings;
opendir my $dir_h, '.'
or die "Cannot open directory: $!";
my #files = grep { /abc/ and not /\.xh$/ } readdir $dir_h;
closedir $dir_h;
print "$_\n" for #files;

Answer 3

opendir(MYDIR, $newpath) or die "$!";
my #files = grep{ !/\.xh$/ && /abc/ } readdir(MYDIR);
close MYDIR;
foreach (#files) {
do something
}

Answer 4

The point that kevinadc and Sinan Unur are using but not mentioning is that readdir() returns a list of all the entries in the directory when called in list context. You can then use any list operator on that. That's why you can use:
my #files = grep (/abc/ && !/\.xh$/), readdir MYDIR;
So:
readdir MYDIR
returns a list of all the files in MYDIR.
And:
grep (/abc/ && !/\.xh$/)
returns all the elements returned by readdir MYDIR that match the criteria there.

Answer 5

foreach $file (#files)
{
my $fileN = $1 if $file =~ /([^\/]+)$/;
if ($fileN =~ /\.xh$/)
{
unlink $file;
next;
}
if ($fileN =~ /^abc/)
{
open(FILE, "<$file");
while(<FILE>)
{
# read through file.
}
}
}
also, all files in a directory can be accessed by doing:
$DIR = "/somedir/somepath";
foreach $file (<$DIR/*>)
{
# apply file checks here like above.
}
ALternatively you can use the perl module File::find.

Answer 6

Instead of using opendir and filtering readdir (don't forget to closedir!), you could instead use glob:
use File::Spec::Functions qw(catfile splitpath);
my #files =
grep !/^\.xh$/, # filter out names ending in ".xh"
map +(splitpath $_)[-1], # filename only
glob # perform shell-like glob expansion
catfile $newpath, 'abc*'; # "$newpath/abc*" (or \ or :, depending on OS)
If you don't care about eliminating the $newpath prefixed to the results of glob, get rid of the map+splitpath.