NAME
          qmail-command - user-specified mail delivery program

     SYNOPSIS
          in .qmailext:  |command

     DESCRIPTION
          qmail-local will, upon your request, feed each incoming mail
          message through a program of your choice.

          When a mail message arrives, qmail-local runs sh -c command
          in your home directory.  It makes the message available on
          command's standard input.

          WARNING: The mail message does not begin with qmail-local's
          usual Return-Path and Delivered-To lines.

          Note that qmail-local uses the same file descriptor for
          every delivery in your .qmail file, so it is not safe for
          command to fork a child that reads the message in the
          background while the parent exits.

     EXIT CODES
          command's exit codes are interpreted as follows:  0 means
          that the delivery was successful; 99 means that the delivery
          was successful, but that qmail-local should ignore all
          further delivery instructions; 100 means that the delivery
          failed permanently (hard error); 111 means that the delivery
          failed but should be tried again in a little while (soft
          error).

          Currently 64, 65, 70, 76, 77, 78, and 112 are considered
          hard errors, and all other codes are considered soft errors,
          but command should avoid relying on this.

     ENVIRONMENT VARIABLES
          qmail-local supplies several useful environment variables to
          command.  WARNING: These environment variables are not
          quoted.  They may contain special characters.  They are
          under the control of a possibly malicious remote user.

          SENDER is the envelope sender address.  NEWSENDER is the
          forwarding envelope sender address, as described in dot-
          qmail(5).  RECIPIENT is the envelope recipient address,
          local@domain.  USER is user.  HOME is your home directory,
          homedir.  HOST is the domain part of the recipient address.
          LOCAL is the local part.  EXT is the address extension, ext.

          HOST2 is the portion of HOST preceding the last dot; HOST3
          is the portion of HOST preceding the second-to-last dot;
          HOST4 is the portion of HOST preceding the third-to-last
          dot.
          EXT2 is the portion of EXT following the first dash; EXT3 is
          the portion following the second dash; EXT4 is the portion
          following the third dash.  DEFAULT is the portion
          corresponding to the default part of the .qmail-...  file
          name; DEFAULT is not set if the file name does not end with
          default.

          DTLINE and RPLINE are the usual Delivered-To and Return-Path
          lines, including newlines.  UFLINE is the UUCP-style From_
          line that qmail-local adds to mbox-format files.

     SEE ALSO
          dot-qmail(5), envelopes(5), qmail-local(8)