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Hi All, Can you please let me know how to grep for a
particular pattern in unix. I want to print the dates from
the file exp.txt. the date pattern is DD:MM:YYYY, I just
want to print all the dates from the file exp.txt.

Question Posted / venkat

Answer Posted / venkat

grep -o -P '(([0-2][0-9]|3[01]):([0][1-9]|[1][012]):[12][09][0-9][0-9])'

use Perl regex to validate the limits of date and month.

Pitfall: it might miss 31st of feb

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