I am doing something which seems very simple to me, yet the regex is not behaving as I had thought it would. The file I am parsing is a fstab, I am trying to ignore commented lines (begin with "#.") I also want to ignore any 'comment' lines which are preceded by whitespace. My example file 

# This file is a comment and should not be used
 # This comment has one leading space
   # This comment has three leading spaces
/dev/mapper/centos-var_log /var/log                xfs     defaults   
+     1 2
 /dev/donstest  /expert         none    1 1 -rw,noglob # this is a fs
 #/dev/donstest22   /expert         none    1 1 -rw,noglob # this is a
+ fS

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and code 

 
#!/usr/bin/perl
use strict;
open (MYFILE, "./file.txt" ) or die "Could not open file:  $! \n";
while ( my $line = <MYFILE> )
{
    chomp $line;
    if  ( $line =~ /^\s*[^#].*/ )
    {
        print "NOT Comment: $line \n";
    }
    else
    {
        print "IS Comment: $line \n";
    }
}

[download]

My output:

IS Comment: # This file is a comment and should not be used
NOT Comment:  # This comment has one leading space
NOT Comment:    # This comment has three leading spaces
NOT Comment: /dev/mapper/centos-var_log /var/log                xfs   
+  defaults        1 2
NOT Comment:  /dev/donstest     /expert         none    1 1 -rw,noglob
+ # this is a fs
NOT Comment:  #/dev/donstest22   /expert         none    1 1 -rw,noglo
+b # this is a fS

[download]

What am I missing? As I understand /^\s*^#/ to mean "match any strings which may have zero of more whitespace characters from line begining followed by any character not a '#' the \s* should be greedy up to the first non-whitespace character. If I replace my regex with /^\s*^#\s ... it works as desired.

In reply to regex whitespace quantifers by halak77

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