You can also use the pure-perl Date::Format module:

perl -MDate::Format -e 'print time2str( "%Y-%m-%e", 192948519 )'
perl -MDate::Format -e 'print time2str( "%Y-%m-%e", 19294851 )'
[download]

Respectively returns:

1976-02-11
1970-08-12
[download]

Chris
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