[SYMBOL] [A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Z] H configuration command  h delivery agent flag  H line (qf file)  H* default for all headers  H_... flags  HACK m4 macro  HAS... compile-time macros  hash database type  headers  2nd      7bit, F=6 delivery agent flag and      Check after all have been processed      checking with rule sets      defining, recommendations for      in queue      maximum length      mc configuration and      message         behavior in conf.c file          defining  [See H configuration command]         getting recipients from          in qf file          mailing lists and      reference guide to      screening          with $          with H*  Hein, Trent R.  HELO command (SMTP)  2nd  help documentation  [See resources for further reading] HES_GETMAILHOST compile-time macro  HESIOD compile-time macro  hesiod database type  hidden dot algorithm  high bit  history of sendmail  HoldExpensive option  holding messages  home directory of recipients  hop count  2nd  hostnames      $@ operator and      canonicalizing  [See canonicalization]     case sensitivity and      default      domain part of, $m macro for      fully qualified  2nd      short form of, $w macro for  2nd  hosts     canonical name of      IP addresses of      masquerading  [See masquerading]     offsite MX      setting      smart  2nd  3rd  4th      sticky and nonsticky  hoststat command  hubs, $H macro for  Hunt, Craig