TCOPY(1)                FreeBSD General Commands Manual               TCOPY(1)

NAME
     tcopy - copy and/or verify mag tapes

SYNOPSIS
     tcopy [-cvx] [-s maxblk] [src [dest]]

DESCRIPTION
     The tcopy utility is designed to copy magnetic tapes.  The only
     assumption made about the tape layout is that there are two sequential
     EOF marks at the end.  By default, the tcopy utility will print
     information about the sizes of records and files found on the /dev/sa0
     tape, or on the tape specified by the src argument.  If a destination
     tape is also specified by the dest argument, a copy of the source tape
     will be made.  The blocking on the destination tape will be identical to
     that used on the source tape.  Copying a tape will yield the same program
     output as if just printing the sizes.

     The following options are available:

     -c               Copy src to dest and then verify that the two tapes are
                      identical.

     -s maxblk        Specify a maximum block size, maxblk.

     -v               Given the two tapes src and dest, verify that they are
                      identical.

     -x               Output all informational messages to the standard error
                      instead of the standard output.  This option is useful
                      when dest is given as /dev/stdout.

SEE ALSO
     mt(1), mtio(4)

HISTORY
     The tcopy command appeared in 4.3BSD.

BUGS
     Writing an image of a tape to a file does not preserve much more than the
     raw data.  Block size(s) and tape EOF marks are lost which would
     otherwise be preserved in a tape-to-tape copy.

     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.

     When using the copy/verify option -c, tcopy does not rewind the tapes
     prior to start.  A rewind is performed after writing, prior to the
     verification stage.  If one does not start at the beginning-of-tape (BOT)
     then the comparison may not be of the intended data.

FreeBSD 13.1-RELEASE-p6        December 20, 2006       FreeBSD 13.1-RELEASE-p6