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TCOPY(1)		     General Commands Manual			TCOPY(1)

NAME
     tcopy -- read, write, copy and verify tapes

SYNOPSIS
     tcopy [-crvx] [-l logfile] [-s maxblk] [src [dest]]

DESCRIPTION
     The tcopy utility is designed to read, write and copy tapes.

     The  only	assumption  made about the tape layout is that there are two se-
     quential EOF marks at the end.

     The src argument can be a tape device and defaults to /dev/sa0 or it can be
     data in SIMH-TAP format.  If src is "-" the standard input is read.

     If the dest argument is also specified, a copy of the src will be made onto
     the dest.	If dest is "-" standard output will be written to.

     If dest is a tape device, the file and record structure will be the same.

     If dest is a filename ending in ".000" the contents each file on  src  will
     be  written to sequentially numbered files ".000", ".001", ".002" etc.  In-
     formation about record sizes will be lost.

     If the -r flag is specified, only the data  will  be  written,  information
     about file and record layout is lost.

     Otherwise	the  data,  file  and record structure of src will be written in
     SIMH-TAP format.

     The tcopy utility will report information about the layout of src like this
     on standard output:

	   file 0: block size 80: 6 records
	   file 0: eof after 6 records: 480 bytes
	   file 1: block size 3072: records 0 to 262
	   file 1: block size 612: record 262
	   file 1: eof after 263 records: 805476 bytes
	   [a|]
	   eot
	   total length: 972851280 bytes time: 41 s rate: 22934.8 kB/s

     If dest is "-" or if -x is specified this goes to standard  error	instead,
     and  can  also be redirected with -l logfile, in which case the final total
     line will also be reported on standard error.

     If tcopy receives a SIGINFO signal, current counts are reported on standard
     error.

     The following options are available:

     -c 	Rewind both tapes, copy src to dest,  rewind  again  and  verify
		that the two tapes are now identical.

     -l logfile
		Output all informational messages to logfile.

     -r 	Write  only  the contents of all data blocks to the output.  The
		file and record structure of the input will be lost.

     -s maxblk	Specify  a  maximum  block  size,  maxblk.    The   default   is
		kern.maxphys.

     -v 	Verify that src and dest are identical.  Note that the tapes are
		not rewound prior to the comparison.

     -x 	Output	all informational messages to the standard error instead
		of the standard output.  This option is  automatic  if	dest  is
		given as "-".

EXIT STATUS
     Unfortunately all over the place, but zero always means succeess.

EXAMPLES
     Verify that the tape in /dev/sa0 can be read and see the layout of its con-
     tent:

	   tcopy

     Copy a tape using two tape drives:

	   tcopy  /dev/sa0 /dev/sa1

     Copy a tape using only a single tape drive, and verify the result:

	   tcopy /dev/sa0 /tmp/temp.tapfile
	   # change tape
	   tcopy -c /tmp/temp.tapfile /dev/sa0

     Make  a  cryptographic hash of both the contents and the layout of the tape
     in /dev/sa1:

	   tcopy /dev/sa1 - | sha256

     Copy a tape to a tape drive on another machine:

	   tcopy /dev/sa0 - | ssh otherhost tcopy - /dev/sa0

     Extract the tape files into individual files:

	   tcopy /dev/sa0 /tmp/_.tape.000

     Ignore all structure on the tape and feed all data to tar(1):

	   tcopy -l /dev/null -r /dev/sa0 - | tar tvf -

SEE ALSO
     mt(1), sa(4), mtio(4)

STANDARDS
     The  SIMH-TAP  format  is	documented  in	the  open-simh	 github   repos:
     https://github.com/open-simh/simh/blob/master/doc/simh_magtape.doc

HISTORY
     The tcopy command appeared in 4.3BSD.

BUGS
     Modern tape drives may return a SCSI "Incorrect Length Indicator (ILI)" for
     each  read  with  a different block size that what is on the tape, and that
     slows tcopy down a lot.  This can be disabled with the mt(1) command:

	   mt param sili -s 1

     End of data (EOD) is determined by two sequential EOF marks  with	no  data
     between  them.   There  used  to be old systems which typically wrote three
     EOF's between tape files.	The tcopy utility will erroneously stop  copying
     early in this case.

     With -c the tape drives are not rewound at the same time, but one after the
     other.

FreeBSD 15.1			December 20, 2006			TCOPY(1)
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