starry, 111 bytes

Result

AC

Duration

921ms

Code [DL]

` , + .        +    *' `     +          + +  * +*  `  + + ,* + .       +    **  +      + * +  '    + , +* + . '

Disassembly

[[:label, 0],
 [:char_in],
 [:dup],
 [:char_out],
 [:push, 3],
 [:%],
 [:jump, 0],
 [:label, 1],
 [:push, 0],
 [:push, 5],
 [:dup],
 [:*],
 [:dup],
 [:+],
 [:label, 2],
 [:swap],
 [:dup],
 [:char_in],
 [:+],
 [:dup],
 [:char_out],
 [:push, 2],
 [:%],
 [:+],
 [:swap],
 [:push, 1],
 [:-],
 [:dup],
 [:jump, 2],
 [:pop],
 [:char_in],
 [:dup],
 [:+],
 [:dup],
 [:char_out],
 [:jump, 1]]

stdin

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                               K                  

stdout

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                               K!"""@             

stderr

/root/starry.rb:65:in `run': undefined method `ord' for nil:NilClass (NoMethodError)
	from /root/starry.rb:13:in `run'
	from /root/starry.rb:154:in `<main>'

strace

11    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffe9c807380 /* 9 vars */) = 0
12    execve("/bin/cat", ["cat", "-"], 0x55597249fd70 /* 9 vars */) = 0
13    execve("/usr/local/ruby-2.6.3/bin/ruby", ["/usr/local/ruby-2.6.3/bin/ruby", "/root/starry.rb", "/volume/CODE"], 0x555974036068 /* 9 vars */) = 0
12    +++ exited with 0 +++
11    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=12, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
13    +++ exited with 1 +++
11    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=13, si_uid=0, si_status=1, si_utime=9, si_stime=4} ---
11    +++ exited with 1 +++