Another option would be to use a tied hash. That way the hash on-disk would be updated in real-time as you manipulated your hash variable. This may be slower (or faster) depending on the number of elements in the hash and the number of times you access the hash: 
use DB_File;
my %db;
tie (%db,'DB_File','./myhashfile.dat') or die "Can't open hash file\n"
+;

# do stuff with %db here

untie %db;

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In reply to Re: dumping hashes to a file by lhoward
in thread dumping hashes to a file by Anonymous Monk

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