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MAGTAPE

CARTRIDGE

8.1;edmtdesc (edit_magtape_descriptor), revision 8.1, 84/10/26
EDMTDESC (EDIT_MAGTAPE_DESCRIPTOR) -- Edit magtape descriptor file.
usage:  EDMTDESC pathname {-C | -L [var...] | -S {var value...}... } {CL}


FORMAT

  EDMTDESC pathname {options}


  EDMTDESC  allows  you  to  create,  list,  and modify magnetic tape descriptor
  objects.  These descriptor files provide information to the streams manager so
  that  it  can handle subsequent tape operations much as an SIO descriptor file
  describes the configuration of an SIO line.


ARGUMENTS

  pathname
  (required)         Specify name of magtape  descriptor  file  to  be  created,
                     listed, or edited.


OPTIONS

  At least one of the following options must be specified.

  -C                  Create a new magtape descriptor object with the name given
                     in the 'pathname' argument.

  -L [var...]        List the values  of  the  variable(s)  specified.    If  no
                     variables  are  named,  the  entire  magtape  descriptor is
                     listed.

  -S {var value}...
                     Set  the  variable(s)  indicated to the specified value(s).
                     At least one variable/value  pair  is  required  if  -S  is
                     specified.    Multiple  variable/value pairs are permitted,
                     separated by blanks.

  This command uses the command line parser, and so also  accepts  the  standard
  command options listed in HELP CL.


  VARIABLES

  The  variables  known to EDMTDESC are listed below, along with their types and
  default values.  The variable  types  are:    integer  (int),  Boolean  (y/n),
  character string of n letters (c [n]), and date (in format yy/mm/dd.hh:mm).

    name    type   default  definition

    DEV     c[1]    M       device type ('M' for magtape, 'C' for cartridge)
    U       int     0       magtape unit number (normally 0)
    LAB     y/n     yes     'yes' if magtape is ANSI labeled, 'no' if
                             unlabeled
    REO     y/n     no      'yes' to reopen previously used volume, 'no'
                             to open new volume ('yes' suppresses rewind)
    CLV     y/n     yes     'yes' closes volume when file is closed,
                             'no' leaves volume open
    SPOS    y/n     no      'yes' saves volume position when volume is
                             closed (for reopen), 'no' rewinds volume
                             when closed
    VID     c[6]    -auto   volume identifier (labeled volumes)
    VACC    c[1]            volume accessibility (labeled volumes)
    OWN     c[14]   -auto   volume owner (labeled volumes)
    F       int*    1       file sequence number -- integer or "cur" for
                             current file, or "end" for new file at end
                             of labeled volume
    RF      c[1]    D       record format -- "F" for fixed length, "D"
                             for variable length, "S" for spanned,
                             "U" for undefined
    BL      int     2048    block length, in bytes
    RL      int     2048    (maximum) record length, in bytes
    ASCNL   y/n     yes     'yes' for ascii newline handling (strip
                             newlines on write, supply them on read),
                             'no' for no newline handling
    FSECT   int     1       file section number (labeled volumes)
    FID     c[17]           file identifier (labeled volumes)
    FSID    c[6]            file set identifier (labeled volumes)
    GEN     int     1       generation of file (labeled volumes)
    GENV    int     1       generation version of file (labeled volumes)
    CDATE   date    -auto   creation date of file (labeled volumes)
    EDATE   date    -auto   expiration date of file (labeled volumes)
    FACC    c[1]            file accessibility (labeled volumes)
    SYSC    c[xx]           system code (labeled volumes)
    SYSU    c[xx]           system use (labeled volumes)
    BOFF    int     0       buffer offset (labeled volumes, should be 0)


  For  cartridge  tape  (DEV  C),  you must change the block length (BL) and the
  record length (RL) to be 512 or  less  and  the  record  format  to  be  fixed
  ('RF F').


EXAMPLES

  $ edmtdesc set_tape -s u 1 lab yes        Edit file "set_tape";
                                             set the tape unit number
                                             to 1; declare tape as
                                             ANSI labeled.

  $ edmtdesc ct -c -s dev c bl 512 rl 128 rf f
                                           Create descriptor file ct for
                                            cartridge tape, blocking 4
                                            records of maximum length 128
                                            to each block.


RELATED TOPICS

  More information is available.  Type:

  - HELP MAGTAPE
   for general information on magnetic tape usage.

  - HELP CARTRIDGE
   for general information on cartridge tape usage and support.

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026