Hello Monks,

Need your help again. I am using grep function to select certain file names in an array using file mask. When I use the a scalar variable as the regular expression pattern in the grep function, I get wrong result. A hard coded pattern returns the right result. Please see the code below.

use strict;
my $folder=".";
my $file_mask="\.txt";
my $file;
opendir(DIR, "$folder");
my @files =grep(/$file_mask$/,readdir(DIR));
closedir(DIR);
foreach $file (@files) {
    print "$file\n";
    # Finds a file called 1txt (WHY)
}

opendir(DIR, "$folder");
@files =grep(/\.txt$/,readdir(DIR));
closedir(DIR);
foreach $file (@files) {
    print "$file\n";
    # Does not find the file called 1txt (As expected)
}

[download]

I would greatly appreciate your input regarding this anomaly.

Ash

In reply to Question: File name pattern match using Grep function by jujiro_eb

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