I was trying the following script for extracting sequences in fasta format from a list of geneID from genbank.
I got that error message when i tried large number of sequence download(some 1000-2000) at a time.
the script does not work for large number of sequence to be extracted at a time.
$space = " ";
my($line) = $_;
$sequence = get_sequence($database, $id);
$test = write_sequence( ">>sequences_1.txt", $format, $sequence);
open (CHK , ">>checking.txt");
print CHK <<HERE;