ZModem standard:
    lrzsz is compatible with standard zmodem as long as you don't use
    certain options:
    -8 is incompatible with the standard, but should work with most
       DOS/Atari/Amiga ZModems. It's a common extension, but a dangerous
       one. Do not use it unless you know that the receiver can handle it.
    -S is incompatible with certain ZModems which use the TIMESYNC bit
       for other purposes (timesync is a protocol extension by Peter
       Mandrella, read timesync.doc for more information). The default
       is to disable timesync, you must use the `S' option to enable it.


Calling conventions:
    lrzsz is not fully compatible with older UNIX ZModems:
    - PUBDIR (/var/spool/uucppublic) is normally disabled. If you like
      public writable directories please use:
        configure --enable-pubdir=/var/spool/uucppublic
    - lrz defaults to restricted mode, in which the sender must not upload
      any files outside the working directory or PUBDIR (if pubdir is
      enabled). With the old version you had to set SHELL=rsh.
      For more information read the SECURITY paragraph in lrz.1.
    - lrz: remote command execution is disabled. To enable it use -C (but
      be careful - the sender might delete all your files).
    - lrz: does not set executable bits for any files it received under
      a restricted shell.
