$ cat /tmp/foo2 | while read line ; do ts=`echo $line | awk '{print $1}'` ; echo -n `gdate -u --date @$ts ` ; echo $line ; done
Mon Aug 5 06:00:00 UTC 20191564984800 89496
Mon Aug 5 07:00:00 UTC 20191564988400 122551
Mon Aug 5 08:00:00 UTC 20191564992000 120459
Mon Aug 5 09:00:00 UTC 20191564995600 9665934
Mon Aug 5 10:00:00 UTC 20191564999200 12854564
Mon Aug 5 11:00:00 UTC 20191565002800 12868717
Mon Aug 5 12:00:00 UTC 20191565006400 12977317
Mon Aug 5 13:00:00 UTC 20191565010000 12921577
Mon Aug 5 14:00:00 UTC 20191565013600 12807037
Mon Aug 5 15:00:00 UTC 20191565017200 12884411
Mon Aug 5 16:00:00 UTC 20191565020800 12972861
Mon Aug 5 17:00:00 UTC 20191565024400 12942224
Mon Aug 5 18:00:00 UTC 20191565028000 12892381
Mon Aug 5 19:00:00 UTC 20191565031600 12989047
Mon Aug 5 20:00:00 UTC 20191565035200 13053705
Mon Aug 5 21:00:00 UTC 20191565038800 13070253
Mon Aug 5 22:00:00 UTC 20191565042400 13019450
Mon Aug 5 23:00:00 UTC 20191565046000 13049684
Tue Aug 6 00:00:00 UTC 20191565049600 13024110
Tue Aug 6 01:00:00 UTC 20191565053200 12982080
Tue Aug 6 02:00:00 UTC 20191565056800 13077342
Tue Aug 6 03:00:00 UTC 20191565060400 12793216
Tue Aug 6 04:00:00 UTC 20191565064000 12838093
Tue Aug 6 05:00:00 UTC 20191565067600 12635238
Tue Aug 6 06:00:00 UTC 20191565071200 12651153
Tue Aug 6 07:00:00 UTC 20191565074800 12767989
Tue Aug 6 08:00:00 UTC 20191565078400 12629391
Tue Aug 6 09:00:00 UTC 20191565082000 12736919
Tue Aug 6 10:00:00 UTC 20191565085600 12894567
Tue Aug 6 11:00:00 UTC 20191565089200 13016745
Tue Aug 6 12:00:00 UTC 20191565092800 12976584
Tue Aug 6 13:00:00 UTC 20191565096400 12779918
Tue Aug 6 14:00:00 UTC 20191565100000 12741628
Tue Aug 6 15:00:00 UTC 20191565103600 12738770
Tue Aug 6 16:00:00 UTC 20191565107200 12791222
Tue Aug 6 17:00:00 UTC 20191565110800 12838313
Tue Aug 6 18:00:00 UTC 20191565114400 12876227
Tue Aug 6 19:00:00 UTC 20191565118000 12901289
Tue Aug 6 20:00:00 UTC 20191565121600 12819658
Tue Aug 6 21:00:00 UTC 20191565125200 12802505
Tue Aug 6 22:00:00 UTC 20191565128800 12887322
Tue Aug 6 23:00:00 UTC 20191565132400 12923086
Wed Aug 7 00:00:00 UTC 20191565136000 12948010
Wed Aug 7 01:00:00 UTC 20191565139600 12895682
Wed Aug 7 02:00:00 UTC 20191565143200 12778783
Wed Aug 7 03:00:00 UTC 20191565146800 12696217
Wed Aug 7 04:00:00 UTC 20191565150400 12600891
Wed Aug 7 05:00:00 UTC 20191565154000 12502945
Wed Aug 7 06:00:00 UTC 20191565157600 12540648
Wed Aug 7 07:00:00 UTC 20191565161200 9004334
Wed Aug 7 08:00:00 UTC 20191565164800 54962
Fri Aug 16 04:00:00 UTC 20191565928000 12661