lrzsz: free x/y/zmodem implementation
lrzsz is a unix communication package providing the
ZMODEM file transfer protocols.
lrzsz is a heavily rehacked version of the last public domain
Omen Technologies rzsz
package, and is now
and released under the
GNU General Public Licence.
Features of lrzsz
- very portable, automagically configured with GNU autoconf.
- crash recovery.
- up to 8KB block sizes (ZMODEM8K).
- internationalized (using GNU gettext). German translation
of the programs output exists.
- far more secure than the original sources.
- high performance. say `make vcheck-z' and have a look at
the BPS rate - i recently saw 1.4 MB per second
transfering a large file through pipes (on a I586/133 system.
- good blocksize calculation (tries to compute an optimal
blocksize based on the number of errors occured).
The lastest release is
lrzsz-0.12.20.tar.gz ((about 270KB)).
- Version 0.12.20 - December 1998, Uwe Ohse
- works on BeOS and stone-aged SCO (sco-3.2v4.2)
- pubdir-"feature" works again.
- "make rpm" creates a rpm file.
- "optimal blklen calculation" was too aggressive, it
now does nothing if the user demands fixed blklens.
- various smaller and medium bug fixes.
- a more or less important security bug is fixed (stupid
use of /tmp in a piece of code which is rarely used).
- lrz uses umask to make files unreadable which receiving them.
- "sh systype | mail firstname.lastname@example.org"
sends a success report with a description of the
- --enable-syslog is now default
- Version 0.12.19 - January 1998, Uwe Ohse
(sorry, i forgot to announce that version here. -- uwe, 9.5.1998)
- 0.12.18 was broken, lsz crashed if receiver found an CRC error.
- lrz options "--rename" and "--escape" didn't work.
- lrz didn't implement senders "overwrite-or-skip" option.
- added dejagnu testsuite. Maybe you need a dejagnu snapshot to use it.
- Version 0.12.18 - November 1997
keep off - this version has a major bug
- syslog output now includes user name.
- new script lrzszbug, to be used for bugreports (untested)
- lots of compiler warnings (egcs -Wparanoia [many -W]) removed.
- new options --tcp-server and --tcp-client ADDRESS:PORT for both programs.
(this is not too much code bloat, and somewhat useful for me - but i
suspect nobody else will need it. Oh well)
- updated to gettext-0.10.32
- updated to automake-1.2
- Version 0.12.17 - August 1997
This version was _not_ put on the ftp/http servers.
- internal cleanup.
- portability enhancements by (Philippe De Muyter <email@example.com>)
- lsz has a new option "--tcp" (no shortopt implemented). lsz transmits
one file over normal stdin/stdout (a control file), then opens a
tcp connection to transmit all other files.
That might be useful if your telnetd is really stupid.
- Version 0.12.16 - March 1997
- major performance improvement (less CPU time needed - don't expect
faster transfers over slow lines). make vcheck now show about 50%
- updated to gettext-0.12.27 and automake-1.1l
(automake-1.1l bug: AC_SUBST in AM_PATH_PROG_WITH_TEST leads
to a "$1=@$1@" line in Makefile.in. I hacked around it in
- Version 0.12.15 - February 1997
- lrzsz now compiles even with pre-ANSI-compilers (tested with
the HPUX 9.00 bundled compiler - what a bad program. Shame on HP).
- lrz supports a new option --o-sync, which forces it to open the
output file in synchronous write mode. Don't use it unless you
are using interrupts if update writes to the disk.
- Version 0.12.14 - January 1997
- lrzsz now compiles cleaner on SCO, HPUX.
- improved error reporting (i think there are still possibilities
for further improvements, if anybody case spare time :-)).
- Version 0.12.13 - January 1997
- no user visible changes. just a maintainance release.
- updated to gettext-0.12.26.
- Version 0.12.12 - January 1997
- lrx and lrb (aka lsz --x/ymodem) now default to 128 byte
block length (to fix interoperatability problems with
some Xmodems [USR courier flash upload]).
- lrz didn't recognize every short option.
- minor performance tweaks.
- replace mktime() if needed.
- updated to autoconf 2.12.
- Version 0.12.11 - October 1996
- lsz/lrz recognize "rshell" as another name for the restricted
- lrz/lsz recognize a new option --stop-at HH:MM (stop
transmission at HH:MM), and --stop-at +N (stop in N seconds).
- lrz/lsz recognize a new option --delay-startup N:
wait N seconds before doing anything.
- doesn't hang anymore on BSD machines after getting a timeout
(BSD restarts system calls after an interrupt - this made
timeout code useless).
- SIGINT handling turned on unter linux too (i still don't
know why it was turned off under linux (and only there)).
- sz - now prints better transfer statistics after if
reading from a pipe.
- Version 0.12.10 - September 1996
- lsz resends init string if it doesn't receive rz's init.
- improved "make check". By Philippe De Muyter <firstname.lastname@example.org>
- "sz -" should work again. This will not work if sz cannot read from
- portability enhancements by Philippe De Muyter <email@example.com>
- Version 0.12.9 - September 1996
- New options --min-bps N and --min-bps-time M: If BPS rate falls under N
for at least M seconds (default: 120) transmission will be stopped.
- added some missing error messages.
- updated manual pages.
- Version 0.12.8 - August 1996
- sz and rz now know about a new option:
-E, --rename: change name if target exists.
- new option -T, --turbo for sz: sz doesn't escape 4 special characters
if this option is given (this should not make problems with any
rz, but could be problematic on certain links where this characters
have to be escaped).
- debugged blocksize calculation.
- -+, --append option fixed.
- enhance portability.
- use VMIN code some day (it's not hard to implement. it's hard
to automagically check if VMIN works. It doesn't on older BSD
- make argv-recognition of X/Y/Z-mode work with
- write a decent documentation.
- i will not say anything about the original unix zmodem sources.
Just look at them and you'll know (even lrzsz is still worse
than i like it to be).
- the zmodem protocol is a pretty good example of a proprietary
- There are some proprietary, undocumented protocol
extensions made by the original author. Furthermore they
are implemented in such a way that nobody else can
extend the protocol in a safe way.
- There is no way to get extensions included into the
- The protocol is not too good designed. It's impossible to extend
it in a safe way to transfer files in both directions.
- Security was not an issue to the author. The ability to
let the receiver execute any command the sender tells
him is nothing more then a really large security hole
(as large as running older sendmail versions). Hackers
dreams came true.
- On the other hand it has some really good points - especially
it is high efficient, and is, if implemented correctly, usable
over a number of transmission channels nobody thought of at
the time the protocol was designed.
Send comments to firstname.lastname@example.org.