YAPE::Regex::Explain can help: 
use strict; 
use warnings; 

use YAPE::Regex::Explain;
print YAPE::Regex::Explain->new('[[\\s(/]ssshd\\s')->explain();

__END__

The regular expression:

(?-imsx:[[\s(/]ssshd\s)

matches as follows:
  
NODE                     EXPLANATION
----------------------------------------------------------------------
(?-imsx:                 group, but do not capture (case-sensitive)
                         (with ^ and $ matching normally) (with . not
                         matching \n) (matching whitespace and #
                         normally):
----------------------------------------------------------------------
  [[\s(/]                  any character of: '[', whitespace (\n, \r,
                           \t, \f, and " "), '(', '/'
----------------------------------------------------------------------
  ssshd                    'ssshd'
----------------------------------------------------------------------
  \s                       whitespace (\n, \r, \t, \f, and " ")
----------------------------------------------------------------------
)                        end of grouping
----------------------------------------------------------------------

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In reply to Re: Reg Exp by toolic
in thread Reg Exp by GS

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