@ARGV = glob 'datafile*';

open my $OUTPUT, '>', 'output_file' or die "Cannot open 'output_file' 
+because: $!";

my %data;
while ( <> ) {
    next unless /^(.+) (\S+)$/;
    push @{ $data{ $1 } }, $2;
    }

for my $key ( sort keys %data ) {
    print join ' ', $key, @{ $data{ $key } }, scalar @{ $data{ $key } 
+}, "columns\n";
    }

[download]

In reply to Re^3: opening many files by jwkrahn
in thread opening many files by wanttoprogram

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