Hello,

I am maintaining an old system with some monitoring scripts written in perl. The fun part is all these scripts are encoded and I could not read them to figure out why they failed from time to time. Here is script text and hexadecimal header. With several hours google search, I understand these are the bleached scripts and people say it is useless to hide source in such way and mention it is easy to decode it. I tried unbleach.pl and it says script is not bleached. I wonder whether it is possible to decode this script. No need to be accurate or runnable, just information of what it is checking, how it is checking. Thanks for any suggestions! 
#!/usr/bin/perl
$_=<<'';y;\r\n;;d;$_=pack'b*',$_;$_=eval;$@&&die$@;$_


root# od -cx check_services
0000000   #   !   /   u   s   r   /   b   i   n   /   p   e   r   l  \
+n
        2123 752f 7273 622f 6e69 702f 7265 0a6c
0000020   $   _   =   <   <   '   '   ;   y   ;   \   r   \   n   ;   
+;
        5f24 3c3d 273c 3b27 3b79 725c 6e5c 3b3b
0000040   d   ;   $   _   =   p   a   c   k   '   b   *   '   ,   $   
+_
        3b64 5f24 703d 6361 276b 2a62 2c27 5f24
0000060   ;   $   _   =   e   v   a   l   ;   $   @   &   &   d   i   
+e
        243b 3d5f 7665 6c61 243b 2640 6426 6569
0000100   $   @   ;   $   _  \n  \t  \t              \t          \t  \
+n
        4024 243b 0a5f 0909 2020 0920 2020 0a09
0000120                  \t          \t  \t  \n  \t  \t      \t
        2020 2020 2009 0920 0a09 0909 0920 2020
0000140  \t      \t  \n      \t  \t  \t      \t  \t          \n  \t  \
+t
        2009 0a09 0920 0909 0920 2009 0a20 0909
0000160  \t          \t          \t  \n  \t  \t      \t  \t  \t  \t
        2009 0920 2020 0a09 0909 0920 0909 2009
0000200  \t  \n              \t              \t  \t  \n      \t
        0a09 2020 0920 2020 0920 0a09 0920 2020
0000220  \t      \t  \t      \n      \t  \t  \t      \t  \t      \t  \
+n
        2009 0909 0a20 0920 0909 0920 2009 0a09
0000240  \t  \t  \t      \t                  \n          \t  \t  \t
        0909 2009 2009 2020 0a20 2020 0909 2009

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In reply to bleach question by roadtest

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