How to count number of rows inside Oracle dump file?
grep -a -A 5 METRICSTposttables table.dmp


outputs:  

METRICSTposttables actions
METRICET 381
METRICSTPost-inst procedural actions
METRICET 381
METRICSTDeferred analyze commands
TABLE "my_table"


Where 381 matched the export count: 

. . exporting table          MY_TABLE        381 rows exported