Your bug report

#20902: [BUG] hang at fifo despite of '-D skip'

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 20902@debbugs.gnu.org.

-- 
20902: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=20902
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