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SKIP command

The SKIP command moves a magnetic tape set forward  over  a  specified
number of files or records, or to the logical end of the tape set.


Format

     @SKIP (DEVICE) dev:  n units

     where:

     dev:      is the name of the tape set or magnetic tape drive that
               you want to move forward.

     n         is the number of files or records over which  you  want
               to skip.  The colon after the device name is optional.

     units     is either FILES or RECORDS, where records are  sections
               of  a  file; or LEOT, to skip to the logical end of the
               tape set, which is the  next  point  on  the  tape  set
               having two adjacent EOF (end-of-file) marks.
                    Default units - FILES


Restrictions

     SKIP With Open Files

          If you have given a CTRL/C to exit from a program  that  has
          opened  a  file in a magnetic tape set and you then give the
          SKIP command for that tape set, the system will first ask if
          you  want  to close the associated file.  You must do so for
          SKIP to succeed, but you will probably be unable to continue
          the  program  from  that  point because the file will now be
          closed.

     RECORDS Argument Used for Unlabeled Tapes Only

          You cannot use the RECORDS argument to the SKIP command when
          using  a labeled tape, because read and write operations for
          labeled tapes always move the tape to  the  beginning  of  a
          file.


Warning

     Skipping Past LEOT (Unlabeled Tapes Only)

          If you specify too large a value for n in the  SKIP  command
          line,  you can move past the logical end of tape (LEOT).  In
          this case, the operator may have to  intervene  before  your
          tape  control  commands will have effect again.  You must be
          sure how many files you have in the tape set if you use SKIP
          n  rather  than  SKIP  LEOT.  This problem can occur for any
          tapes mounted on drives of the form MTAn:, or for  unlabeled
          tapes mounted on drives of the form MTn:.


Related Commands

     BACKSPACE for moving a magnetic tape backward a specified  number
               of files or records

     REWIND    for returning a magnetic tape to its load point

     UNLOAD    for rewinding  a  magnetic  tape  completely  onto  the
               source  reel  (only  for tapes mounted on drives having
               device names of the form MTAn:)


Examples

     1.  Skip over the next 2 files on the magnetic tape you are using
         (mounted on magnetic tape drive MT0:  in this case).

         @SKIP MT0: 2 FILES

     2.  Skip over the next two records on an unlabeled tape.

         @SKIP MTA0: 2 RECORDS

     3.  Use the MOUNT command to ask the operator to mount your  tape
         in  write-enabled  mode,  then  copy 3 files to the tape from
         your directory on structure SNARK:.  Use the  REWIND  command
         to  go  back  to  the beginning, and the SKIP command to skip
         over the first file.  Use the COPY command to have  the  next
         file  (FIL-2)  printed  on  your terminal, then give the SKIP
         command again to skip to the logical  end-of-tape.   You  are
         skipping only one file, FIL-3, in this case.

         @MOUNT TAPE DAY:/WRITE-ENABLED
         [Mount Request DAY Queued, Request-ID 187]
         [Tape set DAY, Volume DAY mounted]
         [DAY: defined as MT0:]
         @REWIND DAY:
         @MOUNT STRUCTURE SNARK:
         Structure SNARK: mounted
         @ACCESS SNARK:
         @COPY SNARK:FIL-1.TAP DAY:
          SNARK:FIL-1.TAP.1 => MT0:FIL-1 [OK]
         @COPY SNARK:FIL-2.TAP DAY:
          SNARK:FIL-2.TAP.1 => MT0:FIL-2 [OK]
         @COPY SNARK:FIL-3.TAP DAY:
          SNARK:FIL-3.TAP.1 => MT0:FIL-3 [OK]
         @REWIND DAY:
         @SKIP DAY: 1
         @COPY DAY: TTY:
          T0: => TTY:

         !THIS IS THE SECOND FILE.!
         @SKIP DAY:LEOT