RZ

Section: User Commands (1)
Updated: OMEN
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NAME

rx, rb, rz - XMODEM, YMODEM, ZMODEM (Batch) file receive

SYNOPSIS

rz [- +1abepqtuv]
rb [- +1abqtuv]
rz [- 1abceqtuv] file
gz file ...
[-][v]rzCOMMAND

DESCRIPTION

This program uses error correcting protocol to receive files over a serial port from a variety of programs running under PC-DOS, CP/M, Unix, and other operating systems. The first form of rz (Receive ZMODEM) receives files with the ZMODEM batch protocol. If the sending program does not support ZMODEM, rz steps down to YMODEM protocol after 50 seconds. This delay can be eliminated by invoking the program as rb . When receiving with XMODEM or YMODEM, Rz accepts either standard 128 byte sectors or 1024 byte sectors (YAM -k option). The user should determine when the longer block length actually improves throughput without causing problems. If extended file information (file length, etc.) is received, the file length controls the number of bytes written to the output dataset (YMODEM only), and the modify time and file mode (iff non zero) are set accordingly. If no extended file information is received, slashes in the pathname are changed to underscore, and any trailing period in the pathname is eliminated. This conversion is useful for files received from CP/M systems. With YMODEM, each file name is converted to lower case unless it contains one or more lower case letters. The second form of rz receives a single file with XMODEM protocol. The user must supply the file name to both sending and receiving programs. Gz is a shell script which calls sz to command Pro-YAM or ZCOMM to transmit the specified files. Pathnames used with gz must be escaped if they have special significance to the Unix shell.
EXAMPLE: gz "-a C:*.c D:*.h" The third form of rz is invoked as rzCOMMAND (with an optional leading - as generated by login(1)). For each received file, rz will pipe the file to ``COMMAND filename'' where filename is the name of the transmitted file with the file contents as standard input. Each file transfer is acknowledged when COMMAND exits with 0 status. A non zero exit status terminates transfers. A typical use for this form is rzrmail which calls rmail(1) to post mail to the user specified by the transmitted file name. For example, sending the file "caf" from a PC-DOS system to rzrmail on a Unix system would result in the contents of the DOS file "caf" being mailed to user "caf". On some Unix systems, the login directory must contain a link to COMMAND as login sets SHELL=rsh which disallows absolute pathnames. If invoked with a leading ``v'', rz will report progress to /tmp/rzlog. The following entry works for Unix 3.0: rzrmail::5:1::/bin:/usr/local/rzrmail If the SHELL environment variable includes rsh or rksh (restricted shell), rz will not accept absolute pathnames or references to a parent directory, will not modify an existing file, and removes any files received in error. If rz 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 q option.

The meanings of the available options are:

1: Use file descriptor 1 for ioctls and reads (Unix only). By default, file descriptor 0 is used for ioctls and reads. This option allows rz to be used with the Professional-YAM $ command and some versions of ncu(1).
a: Convert files to Unix conventions by stripping carriage returns and all characters beginning with the first Control Z (CP/M end of file).
b: Binary (tell it like it is) file transfer override.
c: Request 16 bit CRC. XMODEM file transfers default to 8 bit checksum. YMODEM and ZMODEM normally use 16 bit CRC.
D: Output file data to /dev/null; for testing.
e: Force sender to escape all control characters; normally XON, XOFF, DLE, CR-@-CR, and Ctrl-X are escaped.
p: (ZMODEM) Protect: skip file if destination file exists.
q: Quiet suppresses verbosity.
t tim: Change timeout to tim tenths of seconds.
v: Verbose causes a list of file names to be appended to /tmp/rzlog . More v's generate more output.

EXAMPLES

(Pro-YAM command)

: <ALT-2>
Pro-YAM Command: sz *.h *.c
(This automatically invokes rz on the connected system.)

NOTES

The Unix "ulimit" parameter must be set high enough to permit large file transfers. The TTY input buffering on some systems may not allow long blocks or streaming input at high speed. You should suspect this problem when you can't send data to the Unix system at high speeds using ZMODEM when YMODEM with 128 byte blocks works properly. If the system's tty line handling is really broken, the serial port or the entire system may not survive the onslaught of long bursts of high speed data. The DSZ or Pro-YAM zmodem l numeric parameter may be set to a value between 64 and 1024 to limit the burst length ("zmodem pl128"). 32 bit CRC code courtesy Gary S. Brown.

BUGS

Calling rz from most versions of cu(1) doesn't work because cu's receive process fights rz for characters from the modem. Programs that do not properly implement the specified file transfer protocol may cause sz to "hang" the port for a minute or two. Every reported instance of this problem has been corrected by using ZCOMM, Pro-YAM, or other program with a correct implementation of the specified protocol. Many programs claiming to support YMODEM only support XMODEM with 1k blocks, and they often don't get that quite right. Pathnames are restricted to 127 characters. In XMODEM single file mode, the pathname given on the command line is still processed as described above. The ASCII option's CR/LF to NL translation merely deletes CR's; undos(omen) performs a more intelligent translation.

VMS VERSION

Some of the #includes with file names enclosed with angle brackets <> may need to have the angle brackets changed to "", or vice versa. The VMS version does not set binary mode according to the incoming file type. Non binary file processing consists of stripping all characters beginning with CPMEOF (^Z). The VMS version does not set the file time. At high speeds, VMS sometimes loses incoming characters, resulting in retries and degradation of throughput. The mysterious VMS C Standard I/O Package and RMS may interact to modify file contents unexpectedly. The VMS version does not support invocation as rzCOMMAND . ZMODEM has not yet been implemented on the VMS version.

ZMODEM CAPABILITIES

Rz supports incoming ZMODEM binary (-b), ASCII (-a), protect (-p), and append (-+) requests, and ZMODEM command execution.

FILES

rz.c, rbsb.c, zm.c, zmodem.h source files. /tmp/rzlog stores debugging output generated with -vv option.

This document was created by man2html, using the manual pages.
Time: 18:39:11 GMT, February 23, 2025

RZ