The mail server functions as follows: when a mail message arrives, it is piped to the program blastmailsrv in the .forward file. blastmailsrv parses the mail message, makes a script which calls the network client program, and pipes the results to mailx which sends the results back to the sender of the request. The source is blastmailsrv.l and is written in lex. This may not be the best way to parse a text file, but since the format of the message is very simple, lex is strong enough to do that.
To learn more about the format of the mail message send a mail to blast@ncbi.nlm.nih.gov with the word HELP in the body of the
message. A local copy is kept in ~/man/blastmail. Here is an
example of a mail query:
PROGRAM blastp DATALIB protpart FILTER seg+xnu MATRIX blosum62 BEGIN >sp|P11684|10KS_HUMAN CLARA CELLS 10 KD SECRETORY PROTEIN PRECURSOR (CC10). MKLAVTLTLVTLALCCSSASAEICPSFQRVIETLLMDTPSSYEAAMELFSPDQDMREAGA QLKKLVDTLPQKPRESIIKLMEKIAQSSLCN