NAME

     sz - send a file using the zmodem protocol


SYNOPSIS

     sz [-LNbdefnopqruvy+] [-ci command] [-Ll n] [-t timeout]


OPTIONS

     -L   Use n-byte packets

     -N   Overwrite if source is newer/longer

     -b   Binary file

     -c   Send command for execution

     -d   Convert dot to slash in names

     -e   Escape for all control characters

     -f   Send full path name

     -i   Send command and return immediately

     -l   Flow control every n packets

     -n   Overwrite destination if source is newer

     -o   Use old (16-bit) checksum

     -p   Protect file if it already exists

     -q   Quiet; opposite of verbose

     -r   Resume interrupt file transfer

     -t   Set timeout in tenths of a second

     -u   Unlink file after successful transmission

     -v   Verbose; opposite of quiet

     -y   Yes, clobber existing files

     -+   Append to an existing file


EXAMPLES

     sz file </dev/tty01 >/dev/tty01
                         # Send file


DESCRIPTION

     XMODEM, YMODEM, and ZMODEM are a family  of  protocols  that
     are  widely  used  is  the  MS-DOS  world  for  transferring
     information reliably from one computer to another.   In  all
     of these protocols, a series of bytes are sent from one com-
     puter to the other, and then an acknowledgement is sent back
     to  confirm correct reception.  Checksums are used to detect
     errors so that transmission is reliable even in the face  of
     noisy  telephone  lines.   Sz is a program that sends a file
     sent from another computer using the zmodem  protocol.   The
     file can be received using rz.

     Sz uses the ZMODEM error correcting protocol to send one  or
     more  files  over a dial-in serial port to a variety of pro-
     grams running under MINIX 3, UNIX, MS-DOS,  CP/M,  VMS,  and
     other  operating systems.  It is the successor to XMODEM and
     YMODEM.

     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 end-to-end data  integrity  between
     application  programs.   ZMODEM's  32 bit CRC catches errors
     that sneak into even the most advanced networks.

     Output from another program may be piped to sz for transmis-
     sion by denoting standard input with -:

     "    "ls -l | sz -

     The program output is transmitted with the filename  sPID.sz
     where  PID  is  the  process  ID  of the sz program.  If the
     environment variable ONAME is set, that is used instead.  In
     this case, the command:

     "    "ls -l | ONAME=con sz -ay -

     will send a 'file' to the PC-DOS  console  display.  The  -y
     option  instructs  the receiver to open the file for writing
     unconditionally. The -a option causes the receiver  to  con-
     vert UNIX newlines to PC-DOS carriage returns and linefeeds.
     On UNIX systems, additional information about  the  file  is
     transmitted.   If  the  receiving program uses this informa-
     tion, 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.

     If sz is invoked with $SHELL set and if that  variable  con-
     tains the string rsh or rksh (restricted shell), sz operates
     in restricted mode.  Restricted mode restricts pathnames  to
     the     current     directory     and     PUBDIR    (usually
     /usr/spool/uucppublic) and/or subdirectories thereof.

     The options and flags available are:
    -+
       Instruct the receiver to append  transmitted  data  to  an
       existing file.
    -a
       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.
    -b
       Binary override: transfer file without any translation.
    -c
       Send COMMAND (follows c) to the  receiver  for  execution,
       return with COMMAND's exit status.
    -d
       Change all instances of '.'  to  '/'  in  the  transmitted
       pathname.   Thus,  C.omenB0000  (which  is unacceptable to
       MS-DOS 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.
    -e
       Escape all control characters; normally  XON,  XOFF,  DLE,
       CR-@-CR, and Ctrl-X are escaped.
    -f
       Send  Full  pathname.   Normally  directory  prefixes  are
       stripped from the transmitted filename.
    -i
       Send COMMAND (follows i) to the  receiver  for  execution,
       return Immediately upon the receiving program's successful
       reception of the command.
    -L
       Use ZMODEM sub-packets of length n (follows L). A larger n
       (32  <=  n  <=  1024)  gives slightly higher throughput, a
       smaller one speeds error recovery.   The  default  is  128
       below  300  baud,  256  above 300 baud, or 1024 above 2400
       baud.
    -l
       Wait for the receiver to acknowledge correct data every  n
       (32  <=  n  <= 1024) characters. This may be used to avoid
       network overrun when XOFF flow control is lacking.
    -n
       Send  each  file  if  destination  file  does  not  exist.
       Overwrite  destination  file  if source file is newer than
       the destination file.
    -N
        Send each  file  if  destination  file  does  not  exist.
       Overwrite  destination  file  if  source  file is newer or
       longer than the destination file.
    -o
       Disable automatic selection of 32 bit CRC.
    -p
       Protect existing destination files by skipping transfer if
       the destination file exists.

    -q
       Quiet suppresses verbosity.
    -r
       Resume interrupted file transfer.  If the source  file  is
       longer  than  the destination file, the transfer commences
       at the offset in the source file that equals the length of
       the destination file.
    -t
       Change timeout.  The timeout, in tenths of  seconds,  fol-
       lows, the -t flag.
    -u
       Unlink the file after successful transmission.
    -w
       Limit the transmit window  size  to  n  bytes  (n  follows
       (enw).
    -v
       Verbose causes a list of file  names  to  be  appended  to
       /tmp/szlog.
    -y
       Instruct a  ZMODEM  receiving  program  to  overwrite  any
       existing file with the same name.
    -Y
       Instruct a  ZMODEM  receiving  program  to  overwrite  any
       existing  file  with the same name, and to skip any source
       files that do have a file with the same  pathname  on  the
       destination system.

  Examples
     Below are some examples of the use of sz.

     "    "sz -a *.c

     This single command transfers all .c files  in  the  current
     directory  with  conversion  (-a) to end-of-line conventions
     appropriate to the receiving environment.

     "    "sz -Yan *.c *.h

     Send only the .c and .h files that exist  on  both  systems,
     and  are  newer on the sending system than the corresponding
     version on the receiving system, converting MINIX 3  to  MS-
     DOS text format.


SEE ALSO

     rz(1), term(1).