reading /etc/mailname beyond the first newline can be suboptimal

We like to provide hints to our sysadmins when files are being handled by the configuration management system. The files have their w bits unset, and a warning header is included.

/etc/mailname presented an interesting case - no problem setting it "a-w", but it is specified to contain the system's e-mail domain as the first line. We figured that since the postfix package's scripts only read the first line, we could get away with *appending* the warning header. Unfortunately for us, bzr reads the entire file, which results in e.g.

    pjdc@zucchini:~$ bzr whoami
    Paul Collins <<email address hidden>
    #
    # m
    # mmmm m m mmmm mmmm mmm mm#mm
    # #" "# # # #" "# #" "# #" # #
    # # # # # # # # # #"""" #
    # ##m#" "mm"# ##m#" ##m#" "#mm" "mm
    # # # #
    # " " "
    # This file is managed by puppet. Do not make local changes.>
    pjdc@zucchini:~$ _

(The first few lines are a chunk of ASCII art that says "puppet", if it's coming across as gibberish.)

So it would be helpful to us if bzr were to stop reading /etc/mailname when it encounters a newline.