Your bug report

#36820: grep "[[:cntrl:]]" /proc/1/cmdline works on 2.20 but not 3.3

which was filed against the grep package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 36820@debbugs.gnu.org.

-- 
36820: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=36820
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