lsz.1

支持X/Y/Z Modem协议的传输文件的通讯程序

'\"
'\" Revision Level 
'\" Last Delta     04-21-88
.TH SZ 1 2.6.1996 lrzsz-0.12b
.SH NAME
sx, sb, sz \- XMODEM, YMODEM, ZMODEM file send
.SH SYNOPSIS
sz
.RB [\- +8abdefkLlNnopqTtuvyY ]
.I file ...
.br
sb
.RB [\- adfkqtuv ]
.I file ...
.br
sx
.RB [\- akqtuv ]
.I file
.br
sz
.RB [\- oqtv ]
.B "-c COMMAND"
.br
sz
.RB [\- oqtv ]
.B "-i COMMAND"
.br
sz -TT
.SH DESCRIPTION
.B Sz
uses the ZMODEM, YMODEM or XMODEM error correcting protocol to send
one or more files over a dial-in serial port to a variety of programs running under
PC-DOS, CP/M, Unix, VMS, and other operating systems.

While
.I rz
is smart enough to be called from
.I cu(1),
very few versions of
.I cu(1)
are smart enough to allow
.I sz
to work properly.
Unix flavors of Professional-YAM are available for such dial-out application.


.B Sz
sends one or more files with ZMODEM protocol.

ZMODEM
greatly simplifies file transfers compared to XMODEM.
In addition to a friendly user interface, ZMODEM
provides Personal Computer and other users
an efficient, accurate, and robust file transfer method.

ZMODEM provides complete
.B "END-TO-END"
data integrity between application programs.
ZMODEM's 32 bit CRC catches errors
that sneak into even the most advanced networks.

Advanced file management features include
AutoDownload (Automatic file Download initiated without user intervention),
Display of individual and total file lengths and transmission time estimates,
Crash Recovery,
selective file transfers,
and preservation of
exact file date and length.

Output from another program may be piped to
.B sz
for transmission by denoting standard input with "-":
.ce
ls -l | sz -
The program output is transmitted with the filename sPID.sz
where PID is the process ID of the
.B sz
program.
If the environment variable
.B ONAME
is set, that is used instead.
In this case, the Unix command:
.ce
ls -l | ONAME=con sz -ay -
will send a "file" to the PC-DOS console display.
The
.B -y
option instructs the receiver to open the file for writing unconditionally.
The
.B -a
option
causes the receiver to convert Unix newlines to PC-DOS carriage returns
and linefeeds.


.B Sb
batch sends one or more files with YMODEM or ZMODEM protocol.
The initial ZMODEM initialization is not sent.
When requested by the receiver,
.B sb
supports
.B YMODEM-g
with "cbreak" tty mode, XON/XOFF flow control,
and interrupt character set to CAN (^X).
.B YMODEM-g
(Professional-YAM
.B g
option)
increases throughput over error free channels
(direct connection, X.PC, etc.)
by not acknowledging each transmitted sector.

On
.SM Unix
systems, additional information about the file is transmitted.
If the receiving program uses this information,
the transmitted file length controls the exact number of bytes written to
the output dataset,
and the modify time and file mode
are set accordingly.


.B Sx
sends a single
.I file
with
.B XMODEM
or
.B XMODEM-1k
protocol
(sometimes incorrectly called "ymodem").
The user must supply the file name to both sending and receiving programs.

If
.B sz
is invoked with $SHELL set and iff that variable contains the
string
.I "rsh"
,
.I "rbash"
or
.I "rksh"
(restricted shell),
.B sz
operates in restricted mode.
Restricted mode restricts pathnames to the current directory and
PUBDIR (usually /usr/spool/uucppublic) and/or subdirectories
thereof.


The fourth form sends a single COMMAND to a ZMODEM receiver for execution.
.B Sz
exits with the COMMAND return value.
If COMMAND includes spaces or characters special to the shell,
it must be quoted.


The fifth form sends a single COMMAND to a ZMODEM receiver for execution.
.B Sz
exits as soon as the receiver has correctly received the command,
before it is executed.


The sixth form (sz -TT)
attempts to output all 256 code combinations to the terminal.
In you are having difficulty sending files,
this command lets you see which character codes are being
eaten by the operating system.


If
.B sz
is invoked with stdout and stderr to different datasets,
Verbose is set to 2, causing frame by frame progress reports
to stderr.
This may be disabled with the
.B q
option.
.PP
The meanings of the available options are:
.PP
.PD 0
.TP
.B "-+, --append"
Instruct the receiver to append transmitted data to an existing file
(ZMODEM only).
.TP 
.B "-2, --twostop"
use two stop bits (if possible). Do not use this unless you know
what you are doing.
.TP
.B "-8, --try-8k"
Try to go up to 8KB blocksize. This is incompatible with standard zmodem,
but a common extension in the bbs world. (ZMODEM only).
.TP
.B "--start-8k"
Start with 8KB blocksize. Like --try-8k.
.TP
.B "-a, --ascii"
Convert NL characters in the transmitted file to CR/LF.
This is done by the sender for XMODEM and YMODEM, by the receiver
for ZMODEM.
.TP
.B "-b, --binary"
(ZMODEM) Binary override: transfer file without any translation.
.TP
.B "-B NUMBER, --bufsize NUMBER"
Use a readbuffer of 
.B NUMBER
bytes. Default ist 16384, which should be enough
for most situations. If you have a slow machine or a bad disk interface
or suffer from other hardware problems you might want to increase
the buffersize.
.B -1
or
.B auto
use a buffer large enough to buffer the whole file. Be careful with this
option - things normally get worse, not better, if the machine starts
to swap.

Using this option turns of memory mapping of the input file. This
increases memory and cpu usage.
.TP
.B "-c COMMAND, --command COMMAND"
Send COMMAND to the receiver for execution, return with COMMAND\'s exit status.
.TP
.B "-C N, --command-tries N"
Retry to send command N times (default: 11).
.TP
.B "-d, --dot-to-slash"
Change all instances of "." to "/" in the transmitted pathname.
Thus, C.omenB0000 (which is unacceptable to MSDOS or CP/M)
is transmitted as C/omenB0000.
If the resultant filename has more than 8 characters in the stem,
a "." is inserted to allow a total of eleven.

This option enables the 
.B "--full-path"
option.
.TP
.B "--delay-startup N"
Wait
.B N
seconds before doing anything.
.TP
.B "-e, --escape"
Escape all control characters;
normally XON, XOFF, DLE, CR-@-CR, and Ctrl-X are escaped.
.TP 
.B"-E, --rename"
Force the sender to rename the new file if a file with the same
name already exists.
.TP
.B "-f, --full-path"
Send Full pathname.
Normally directory prefixes are stripped from the transmitted
filename.

This is also turned on with to 
.B "--dot-to-slash"
option.
.TP
.B "-h, --help"
give help.
.TP
.B "-i COMMAND, --immediate-command COMMAND"
Send COMMAND to the receiver for execution, return immediately
upon the receiving program's successful recption of the command.
.TP
.B "-k, --1k"
(XMODEM/YMODEM) Send files using 1024 byte blocks
rather than the default 128 byte blocks.
1024 byte packets speed file transfers at high bit rates.
(ZMODEM streams the data for the best possible throughput.)
.TP
.B "-L N, --packetlen N"
Use ZMODEM sub-packets of length N.
A larger N (32 <= N <= 1024) gives slightly higher throughput,
a smaller N speeds error recovery.
The default is 128 below 300 baud, 256 above 300 baud, or 1024 above 2400 baud.
.TP 
.B "-m N, --min-bps N"
Stop transmission if BPS-Rate (Bytes Per Second) falls below N for a 
certain time (see --min-bps-time option).
.TP
.B "-M N, --min-bps-time"
Used together with --min-bps. Default is 120 (seconds).
.TP
.B "-l N, --framelen N"
Wait for the receiver to acknowledge correct data every
.B N
(32 <= N <= 1024)
characters.
This may be used to avoid network overrun when XOFF flow control is lacking.
.TP
.B "-n, --newer"
(ZMODEM) Send each file if
destination file does not exist.
Overwrite destination file if
source file is newer than the destination file.
.TP
.B "-N, --newer-or-longer"
(ZMODEM) Send each file if
destination file does not exist.
Overwrite destination file if
source file is newer or longer than the destination file.
.TP
.B "-o, --16-bit-crc"
(ZMODEM) Disable automatic selection of 32 bit CRC.
.TP
.B "-O, --disable-timeouts"
Disable read timeout handling. This makes lsz hang if the other side
doesn't send anything, but increases performance (not much) and
decreases system load (reduces number of system calls by about 50
percent).