TOPS-20 Commands Reference Manual

MOUNT

Requests that a specified file structure or magnetic tape set be made available for your job's use.

Format

@MOUNT medium (NAME) dev:  /switch(es)

where:

medium is one of the following:
STRUCTURE for mounting file structures (disk packs)
TAPE for mounting magnetic tapes
dev: is either the structure identification (or alias), or the tape setname. The colon after the device name is optional.
/switches are keywords, chosen from the list below, indicating your choice of MOUNT command options.
Summary of MOUNT Command Switches (defaults in boldface)
/CHECK-SETNAME
/DENSITY: 200
556
800
1600
6250
SYSTEM-DEFAULT
/DRIVE-TAPE: 7-TRACK
9-TRACK
/LABEL-TYPE: ANSI
BYPASS
EBCDIC
TOPS-20
UNLABELED
/NEW
/NOUNLOAD
/NOWAIT
/OPERATOR
/PROTECTION:octal protection code Default code - 770000
/READ-ONLY Default - unless /NEW or /SCRATCH specified
/REMARK:119-character remark
/SCRATCH
/START: NUMBER number
VOLID volid
Default number - 1
/STRUCTURE-ID:structure identification
/VOLIDS:list of volids
/WRITE-ENABLED Default - if /NEW or /SCRATCH specified

The switches /NOWAIT and /REMARK are useful with either the STRUCTURE or TAPE medium, while /STRUCTURE-ID is for STRUCTURE only; the other switches are for TAPE only.

MOUNT Command Switches
/CHECK-SETNAME ensures that the setname of the mounted tapes matches the setname you specify as the "dev:" argument to the MOUNT command; otherwise an error will be generated. For labeled tapes only.
/DENSITY: 200
556
800
1600
6250
SYSTEM-DEFAULT
specifies the density, in bits per inch, at which the tape set is to be read or written. Densities 200 and 556 are for unlabeled tapes only. SYSTEM-DEFAULT, one of the values shown (usually 1600), is established at system start-up time.
/DRIVE-TAPE: 7-TRACK
9-TRACK
specifies the type of drive on which the tape set is to be mounted. Labeled tapes must be mounted on 9-track drives.
/LABEL-TYPE: ANSI
BYPASS
EBCDIC
TOPS-20
UNLABELED
tells the system to read and write the tape set according to the specified label standard: ANSI; EBCDIC - IBM TYPES (IN READ-ONLY MODE); TOPS-20 - a superset of ANSI used in TOPS-20 systems; UNLABELED - for unlabeled tapes only. BYPASS (for privileged users only) lets you read and write any tape, labeled or unlabeled, without any label processing.
/NEW tells the system that you are creating a new file set on an existing tape set, whose setname is then changed to be the name you specify as the dev: argument to the MOUNT command. (If the tape set has more than one volume, remember to specify their volids using the /VOLIDS or /OPERATOR switch.) The /CHECK-SETNAME and /READ-ONLY switches are ignored if present, and /WRITE-ENABLED is assumed. Do not give the /START switch if you give /NEW.
/NOUNLOAD asks the system not to unload a volume (reel) of tape from its tape drive when the drive is released by a volume switch (change of volumes required by a read or write operation) or DISMOUNT command. Use this switch to facilitate processing when sufficient drives are available.
/NOWAIT tells the system to return your terminal to TOPS-20 command level as soon as you give the MOUNT command, and to send a message to your terminal when the request has been processed. Otherwise, your terminal waits for the message.
/OPERATOR asks the operator to specify to the system the volids of the tape set you wish to mount. Do not use if you have given the /VOLIDS switch.
/PROTECTION:code specifies a 6-digit octal protection code for new volumes of tape written during the current mount request. The owner always has full access to his tapes, so the first two digits are always interpreted as "77"; also, user groups and directory groups have no effect on tape access, so the middle two digits are always interpreted as "00". Therefore, although six digits can be specified, only the last two digits affect the tape's protection code.

(If you specify only two digits, these will be used as the last two digits of the protection code.) These two digits should be the sum of the values corresponding to the modes of access you want to allow, chosen from the following list:

40 read files in the file set
10 overwrite or modify files in the file set
04 append files to the end of the file set

For tapes of label-type TOPS-20 only.

Default code - 770000

/READ-ONLY ensures that all volumes in the tape set will be mounted without write rings, to prevent accidental erasures.

Default except when /NEW or /SCRATCH is specified

/REMARK:"remark" sends the specified remark to the operator when he is notified of your mount request. The text of the remark must be enclosed in quotation marks (" ") and can be up to three, 80-character lines long (including the MOUNT command line). Note that while the entire remark is displayed on the operator's terminal, only the first line appears in the INFORMATION MOUNT-REQUESTS display.

For structures, the remark will be sent only if the structure must be put on line or physically mounted to satisfy your mount request.

/SCRATCH same as /NEW, except that the volumes in the file set you create will be drawn from the pool of scratch tapes (tapes not presently owned by a particular user), rather than from volumes you specify. Use this switch to create a new file set when you are not supplying the volumes of tape to be used.
/START: NUMBER number
VOLID volid
tells the system which volume (reel) of tape to mount first when satisfying your request. (You must also give the /VOLIDS switch, specifying the group of volumes you will be using.) Use the NUMBER argument to give the order of this volume within the group (e.g., 1 for first, 2 for second), or give the VOLID argument to repeat the volid explicitly. You can use this switch to save time and expense when you know which volume you will be using first.

Default - NUMBER 1

/STRUCTURE-ID:structure identification gives the name of the structure as recorded in the disk(s); used when you gave an alias different from the structure identification as argument "dev:", above. See Hints - Using the /STRUCTURE-ID Switch, below. For privileged users only.
/VOLIDS:volid, volid,... specifies the volids (volume identifiers) of the volumes (reels) of tape you want to access. These must be consecutive volumes, usually of the tape set specified as the "dev:" argument to the MOUNT command. Although you need not specify every volume in the set, any volume not specified will not be accessible. Do not use this switch if you have given the /OPERATOR switch. See also Characteristics - Using the /VOLIDS Switch, below.
/WRITE-ENABLED ensures that all volumes in the tape set will be mounted with write rings.

Default when /NEW or /SCRATCH is specified

Characteristics

Action of MOUNT STRUCTURE Command
If the Structure Has Already Been Mounted

If the structure for which you give the MOUNT command is currently mounted, the system simply increases by 1 the mount count (the number of users who have given the MOUNT but not the DISMOUNT command for the structure), and returns your terminal to TOPS-20 command level. A structure is not ordinarily dismounted until its mount count is 0.

If the Structure Has Not Yet Been Mounted

If the structure for which you give the MOUNT command is not currently mounted, your request stays in the mount request queue until it is acted upon by the operator or until you cancel the request.

Setnames (File Set Identifiers)

The setname, or file set identifier of a set of tapes, is part of the label information written into each volume of the set. It is rewritten every time the /NEW or /SCRATCH switch is included in a MOUNT command. The "dev:" argument of the MOUNT command becomes the setname in this case. If you add volumes to an existing tape set, the system uses the setname of the old volumes as the setname of the new ones.

Using the /CHECK-SETNAME Switch

If you give the MOUNT command to use an existing file set (you do not specify the /NEW or /SCRATCH switch), you can give the /CHECK-SETNAME switch to be sure that the setname written on the tapes matches the setname you specify as the "dev:" argument to the MOUNT command. However, because more than one set of tapes can have the same setname, the /CHECK-SETNAME switch does not ensure that the correct tape set will be mounted. For information about ensuring that the correct tapes are mounted, see Characteristics - Using the /VOLIDS Switch, below.

Volids (Volume Identifiers)

The volid, or volume identifier of a volume (reel) of labeled tape, is part of the label information written into each volume of tape. It is written only once, by the operator during the tape's initialization procedure, and is not changed during the life of the tape. (You should also affix a paper label displaying the volid onto each reel of tape.) You can get a list of volids for previously specified or newly written volumes in any mounted tape set by giving the INFORMATION VOLUMES command for that set.

Using the /VOLIDS Switch

If you give the MOUNT command to use an existing multi-volume tape set (you do not specify the /SCRATCH switch), you can give the volid of each volume you want to use as an argument to the /VOLIDS switch. The system ensures that the correct volumes of a labeled tape will be mounted for your job as long as you use the /VOLIDS switch to specify them. (If the tape set does not consist of labeled tapes, the system does not ensure that the correct tapes are mounted.)

The volids must represent consecutive volumes and must be specified in the order written (oldest first). Note that in general you cannot rely on any apparent alphanumerical order when specifying the volids but must maintain your own list of the volids in each tape set. (See Hints - Keeping Track of Volids, below.) You need not specify every volid in the tape set, but any volume not specified will not be accessible through the current MOUNT command. See also Characteristics - Using the /OPERATOR Switch, and Special Cases - Single-volume Tape Sets, below.

Using the /OPERATOR Switch

You can use the /OPERATOR switch instead of the /VOLIDS switch when asking the system to mount a multi-volume set of tapes. The /OPERATOR switch sends a message to the operator asking him to specify the volid of each volume himself. You must be sure to supply the operator with a list of the volids you want him to specify before giving a MOUNT command that contains the /OPERATOR switch.

Hints

Checking Whether Operator is Present

You can give the INFORMATION SYSTEM-STATUS command to find out whether the operator is in attendance and can process your mount request. Even if the operator is not in attendance, your request remains valid until he returns and deals with it in some way.

Using the /STRUCTURE-ID Switch

The /STRUCTURE-ID switch (available only to users with enabled WHEEL or OPERATOR capabilities) gives the name of the structure as recorded in the disk(s) of the structure itself, where it is used by the system for identification. Be sure that the structure identification is also written with a felt-tip marker on the upper surface of each disk pack, and on a gummed label on the pack cover.

Unless you give this switch, the system mounts the structure with its structure identification as alias. (The alias is the name you use when specifying the structure in file specifications and commands; the INFORMATION STRUCTURE and INFORMATION AVAILABLE DEVICES commands list structures by alias only.) The /STRUCTURE-ID switch allows an enabled WHEEL or OPERATOR to mount a structure under a name different from the one recorded in the structure.

Use this switch for mounting a structure whose structure identification is the same as the alias of a currently mounted structure. In such cases give the MOUNT STRUCTURE command with any unique alias as the "dev:" argument, and specify the structure identification with the /STRUCTURE-ID switch. In subsequent file specifications and commands referring to the structure, use the alias only.

Dummy "dev:" Arguments for Mounting Tapes

If you want to use different tape sets on successive runnings of a single program, you can refer to those tape sets as a logical name in the program, and use this logical name as the "dev:" argument of your MOUNT command when mounting tapes. As long as you also specify the volid of each volume of tape with the /VOLIDS switch (or use the /OPERATOR switch to ask the operator to do so), you need not give the actual setname of the tape set as the "dev:" argument to the MOUNT command. The system considers the "dev:" argument you supply to be a logical name defined as the mounted tape set. Therefore, your program can access the tape set using this logical name.

Keeping Track of Volids

Unless your site has a tape cataloging facility, you must keep your own record of the volids in each of your tape sets. After creating a file set on a new tape set, i.e, one not previously owned by you (by giving the MOUNT command and including the /SCRATCH switch), you should give the INFORMATION VOLUMES command for the set before giving the DISMOUNT command. The system will respond by printing a list at your terminal of the volids of all volumes in the tape set. Similarly, if you mount an old tape set and then perform write operations, you should give INFORMATION VOLUMES before giving DISMOUNT to learn the volids of any volumes added to the set. Keep an ordered list of these volids in a disk file in your directory, for use in subsequent MOUNT commands when you give the /VOLIDS switch.

Special Cases

Single-volume Tape Sets

If the tape set you want to mount consists of a single volume of tape, you need not give the /VOLIDS or /OPERATOR switch to specify its volid. You can give the volid as the "dev:" argument to the MOUNT command.

Structures Unavailable for Mounting

If the operator has given the OPR program command, SET STRUCTURE UNAVAILABLE for a specified structure, the system sends an error message including the phrase, "Structure unavailable for mounting" in response to subsequent MOUNT commands for the structure.

Restrictions

Using SET TAPE Commands

The TOPS-20 SET TAPE DENSITY and SET TAPE PARITY commands are applicable to unlabeled tapes only (but see also Warnings - /DENSITY Switch Has Limited Effect for Unlabeled Tapes, below). The SET TAPE FORMAT and SET TAPE RECORD-LENGTH commands are applicable to both labeled and unlabeled tapes, but to labeled tapes only if they are mounted using the /LABEL-TYPE:ANSI or /LABEL-TYPE:TOPS-20 switch. In addition, the files that you read from or write to such a labeled tape must be in 36-bit format, and they must not have the ;FORMAT attribute as part of their specification.

Warnings

POP Command Cancels Unsatisfied Mount Requests

If you have given a PUSH command to obtain a new level of TOPS-20 and then give a MOUNT command within that new level, a subsequent POP command will cancel your mount request. However, if the specified structure or tape set has already been mounted, it will remain mounted despite your POP command.

/DENSITY Switch Has Limited Effect for Unlabeled Tapes

The /DENSITY switch, when given in a MOUNT command for an unlabeled tape, ensures only that your tape set will be mounted on a drive that supports the specified density. It does not ensure that the tape set will be read or written at this density. To specify the density at which unlabeled tapes are to be read and written, give the SET TAPE DENSITY command.

Effect on Terminal

The MOUNT command with the /NOWAIT switch, leaves your terminal at TOPS-20 command level. If you have not given the /NOWAIT switch, your terminal waits until the system has processed your request, or to return to TOPS-20 command level. This CTRL/C does not cancel your request.

Related Commands

CANCEL for withdrawing mount requests before they are processed
DISMOUNT for giving up access to a particular tape drive or disk drive
INFORMATION AVAILABLE DEVICES for finding out just the names of structures available for mounting (these are listed after DSK and PS, and before the line printers (LPT, LPT0, etc.))
INFORMATION MOUNT-REQUESTS for finding out information about pending mount requests for structures and tape sets, and about currently mounted tape sets
INFORMATION STRUCTURE for finding out information about currently mounted structures
INFORMATION VOLUMES for finding out the volids of all mounted volumes (including newly created volumes) of a tape set
SET TAPE commands for establishing job-wide defaults for tape density, format, parity, and record length

Examples

  1. Mount a structure (it is already physically mounted).
  2. @MOUNT STRUCTURE SNARK:
    Structure SNARK: mounted
    
  3. Mount a structure that is not yet physically mounted. After completing the command, give CTRL/Cs to return to TOPS-20 command level.
  4. @MOUNT STRUCTURE PYBL:
    [Mount Request PYBL Queued, Request-ID 205]
    [MOUNT request remaining in queue]
    ^C
    
  5. Mount a structure, then give CTRL/Cs to return to TOPS-20 command level and cancel the mount request.
  6. @MOUNT STRUCTURE PYBL:
    [Mount Request PYBL Queued, Request-ID 136]
    [MOUNT request remaining in queue]
    ^C
    @CANCEL MOUNT 136
    [1 mount request canceled]
    
  7. Find out what structures are available for mounting (these are listed after DSK and PS and before the line printers), and mount one of these.
  8. @INFORMATION AVAILABLE DEVICES
    Devices available to this job:
     DSK, PS, LANG, TYM, MISC, SNARK, REL4, LPT, LPT0
     LPT1, CDR, CDP, PCDP0, FE0, FE4-15, PTY7-10
     PTY23-61, NUL, PLT, PLT0, DCN, SRV 
    Devices assigned to/opened by this job: TTY220
    @MOUNT STRUCTURE REL4: /NOWAIT
    Structure REL4: mounted
    
  9. Ask that a new tape set be created for you from scratch tapes, and copy some files to it. Before dismounting the tape set, find out the volids of the tape volumes you were assigned.
  10. @MOUNT TAPE LAT: /SCRATCH/LABEL-TYPE:TOPS-20
    [Mount Request LAT Queued, Request-ID 104
    [Tape set LAT, volume LAT mounted]
    [LAT: defined as MT3:]
    @COPY DN20A-11.SYS LAT:
     DN20A-11A.SYS.1 => MT3:DN20A-11A.SYS.131071 [OK]
     DN20A-11B.SYS.1 => MT3:DN20A-11B.SYS.131071 [OK]
     DN20A-11C.SYS.1 => MT3:DN20A-11C.SYS.131071 [OK]
    @INFORMATION VOLUMES LAT:
    Volumes of tape set LAT: 01P02,00L16
    @DISMOUNT TAPE LAT:
    [Tape dismounted, logical name LAT: deleted]
    
  11. Find out if any tape drives can be used without giving the MOUNT command (any such drives will be of the form MTAn). Assign one of these and use the PLEASE program to ask the operator to mount your (unlabeled) tape on this drive. Set the necessary tape parameters, position the tape, and copy a file from tape to the line printer. Then give up the resources you have been using.
  12. @INFORMATION AVAILABLE DEVICES
    Devices available to this job:
     DSK, PS, LANG, TYM, MISC, SNARK, REL4, MTA5, LPT, LPT0, LPT1
     CDR, CDP, PCDP0, FE0, FE4-15, PTY23-61, NUL, PLT
     PLT0, DCN, SRV
    Devices assigned to/opened by this job: TTY220
    @ASSIGN MTA5:
    @PLEASE
    Enter text, terminate with CTRL/Z to wait for response, 
    or ESCape to send message and exit 
    PLEASE MOUNT MY TAPE NAMED UNLBLD IN READ-ONLY MODE ON MTA5:,
    WHICH I HAVE ASSIGNED TO MY JOB.  MTA5: IS A 7-TRACK 
    DRIVE THAT SUPPORTS TAPE DENSITIES OF 800 BPI, CORRECT?
    [PLSOPN Operator at GIDNEY has been notified at 14:34:26]
    @SET TAPE DENSITY 800
    @SET TAPE RECORD-LENGTH 128
    @REWIND MTA5:
    @SKIP MTA5: 4 FILES
    @COPY MTA5: LPT:
     MTA5: => LPT: [OK]
    @UNLOAD MTA5:
    @DEASSIGN MTA5:
    
  13. Perform the same task using the same volume of tape as in the previous example by using the MOUNT command. Note that you still cannot specify a particular tape file by name when the tape is an unlabeled tape.
  14. @MOUNT TAPE UNLBLD: /LABEL-TYPE:UNLABELED/DENSITY:800/DR -
    I'VE-TYPE:7-TRACK
    [Mount Request UNLBLD Queued, Request-ID 128]
    [Tape set UNLBLD, volume UNLBLD mounted]
    [UNLBLD: defined as MT3:]
    @INFORMATION MOUNT-REQUESTS/USER
    
    Tape/Disk Mount Queue:
    Volume    Status  Type   Write   Req Name  Req#  Job#  User          
    -------  -------  ----  -------  --------  ----  ----  -----
    UNLBLD     MTA4  Tape   Locked   UNLBLD    128    55   LATTA
    There is 1 Request in the Queue
    @REWIND UNLBLD:
    @SKIP UNLBLD: 4 FILES
    @COPY UNLBLD: LPT:
     MT3:..4 => LPT: [OK]
    @DISMOUNT TAPE UNLBLD:
    [Tape dismounted, logical name UNLBLD: deleted]
    
  15. Mount a labeled tape containing the same files as in the previous two examples, and perform the same task. Note that you need not specify tape parameters in this MOUNT command, as this information is present in the tape labels and is read automatically. Also, the system ensures that the correct volume of tape is used. Finally, you can specify the tape file by name when using labeled tapes.
  16. @MOUNT TAPE LBLD: /LABEL-TYPE:ANSI/VOLIDS:00115
    [Mount Request LBLD Queued, Request-ID 133]
    [Tape set LBLD, volume 00115 mounted]
    [LBLD: defined as MT3:]
    @INFORMATION MOUNT-REQUESTS/USER
    Tape/Disk Mount Queue:
    Volume    Status  Type   Write   Req Name  Req#  Job#  User         
    -------  -------  ----  -------  --------  ----  ----  -----
    00115     MTA0    Tape   Locked  LBLD       133    55  LATTA
    There is 1 Request in the Queue
    @REWIND LBLD:
    @COPY LBLD:COMPR.BRN LPT:
     MT3:COMPR.BRN.13107 => LPT:COMPR [OK]
    @DISMOUNT TAPE LBLD:
    [Tape dismounted, logical name LBLD: deleted]
    
  17. Mount a two-volume tape set (using the NOUNLOAD switch to simplify volume changes) and overwrite any existing files with new files. Then rewind the tape set. Give various INFORMATION commands as you proceed, to verify logical name and device assignments and to determine whether new volumes have been written.
  18. @MOUNT TAPE LAT: /WRITE-ENABLED/NOUNLOAD/NOWAIT/VOL-
    IDS:DBL01, DBL02
    [Mount Request LAT Queued, Request-ID 19]
    [Tape set LAT, volume DBL01 mounted]
    [LAT: defined as MT0:]
    @INFORMATION MOUNT-REQUESTS /USER
    
    Tape/Disk Mount Queue:
    Volume    Status   Type   Write   Req Name  Req#  Job#  User
    -------  --------  ----  -------  --------  ----  ----  -----
    DBL01    MTA1      Tape  Enabled  LAT         19     7  LATTA
    There is 1 Request in the Queue
    @INFORMATION AVAILABLE DEVICES
    Devices available to this job:
     DSK, PS, LANG, SNARK, NTWORK, REL4, MISC, PACKAG, MTA5
     MT0, LPT, LPT0, LPT1, CDP, PCDP0, FE0, FE2-15, PTY13-61
     NUL, PLT, PLT0, DCN, SRV
    Devices assigned to/opened by this job: MT0, TTY217
    @INFORMATION LOGICAL-NAMES JOB
    LAT: => MT0:
    SYS: => DSK:,SYS:
    @REWIND LAT: /ENTIRE-VOLUME-SET
    @COPY HLP:.HLP LAT:
     PS:<HELP>ACCT20.HLP.1 => MT0:ACCT20.HLP.131071 [OK]
     PS:<HELP>ACCTPR.HLP.1 => MT0:ACCTPR.HLP.131071 [OK]
         .
         .
         .
     PS:<HELP>WAIT.HLP.2 => MT0:WAIT.HLP.131071 [OK]
     PS:<HELP>WATCH.HLP.6 => MT0:WATCH.HLP.131071 [OK]
    @INFORMATION MOUNT-REQUESTS /USER
    Tape/Disk Mount Queue:
    Volume    Status   Type   Write   Req Name  Req#  Job#  User
    -------  --------  ----  -------  --------  ----  ----  -----
    DBL02    MTA3      Tape  Enabled  LAT         19     7  LATTA
    There is 1 Request in the Queue
    
    @INFORMATION VOLUMES LAT:
    Volumes of tape set LAT: DBL01,DBL02
    @REWIND LAT: /ENTIRE-VOLUME-SET
    @INFORMATION MOUNT-REQUESTS /USER
    
    Tape/Disk Mount Queue:
    Volume    Status   Type   Write   Req Name  Req#  Job#  User
    -------  --------  ----  -------  --------  ----  ----  -----
    DBL01    MTA1      Tape  Enabled  LAT         19     7  LATTA
    There is 1 Request in the Queue
    
  19. (For privileged users only.) Enable your capabilities and call the OPR program, then give the PUSH command to OPR. (This action puts you at TOPS-20 command level, but allows you also to see the OPR messages caused by your TOPS-20 commands.) Repeat the write operations of the previous example, then dismount the tape set and exit from the OPR program. Notice that, because of the /NOUNLOAD switch in your original MOUNT command, both volumes of your tape set remain mounted on their drives. Therefore, you can mount the tapes again without operator assistance.
  20. @ENABLE
    $OPR
    OPR>PUSH
    
     TOPS-20 Command processor 7(7)
    @REWIND LAT: /ENTIRE-VOLUME-SET
    @COPY HLP:. LAT:
     PS:<HELP>ACCT20.HLP.1 => MT0:ACCT20.HLP.131071 [OK]
     PS:<HELP>ACCTPR.HLP.1 => MT0:ACCTPR.HLP.131071 [OK]
         .
         .
         .
     PS:<HELP>CHKPNT.HLP.1 => MT0:CHKPNT.HLP.131071 
    15:11:55          --Tape Drive Released By User--
                    MTA1: Volume DBL01 Remaining mounted on drive
    
    15:11:57          --MTA3: Given to Request 19--
                     Volume DBL02 now in use by
                     User LATTA, Job 7, Terminal 217
     [OK]
     PS:<HELP>COBDDT.HLP.6 => MT0:COBDDT.HLP.131071 [OK]
         .
         .
         .
     PS:<HELP>WAIT.HLP.2 => MT0:WAIT.HLP.131071 [OK]
     PS:<HELP>WATCH.HLP.6 => MT0:WATCH.HLP.131071 [OK]
    @INFORMATION VOLUMES LAT:
    Volumes of tape set LAT: DBL01,DBL02
    @INFORMATION MOUNT-REQUESTS /USER
    
    Tape/Disk Mount Queue:
    Volume    Status   Type   Write   Req Name  Req#  Job#  User
    -------  --------  ----  -------  --------  ----  ----  -----
    DBL02    MTA3      Tape  Enabled  LAT         19     7  LATTA
    There is 1 Request in the Queue
    
    @REWIND LAT: /ENTIRE-VOLUME-SET
    
    15:14:51          --Tape Drive Released By User--
                    MTA3: Volume DBL02 Remaining mounted on drive
    
    15:14:51          --MTA1: Given To Request 19--
                     Volume DBL01 now in use by
                     User LATTA, Job 7, Terminal 217
    
    @DISMOUNT TAPE LAT:
    [Tape dismounted, logical name LAT: deleted]
    15:15:21          --Tape Drive Released By User--
                    MTA1: Volume DBL01 Remaining mounted on drive
    @POP
    OPR>EXIT
    $DISABLE
    
  21. Mount the same tape set as in the previous examples, but ask the operator to specify the volids. Use the PLEASE program to help you.
  22. @MOUNT TAPE LAT: /WRITE-ENABLED/NOUNLOAD/NOWAIT/OPERATOR
    [Mount Request LAT Queued, Request-ID 197]
    @PLEASE
    Enter text, terminate with CTRL/Z to wait for response,
    or ESCape to send message and exit
    PLEASE ENTER THE VOLIDS OF MY TAPE SET LAT: FOR
    REQUEST 197.  THEY ARE RECORDED IN YOUR TAPE
    LIBRARY CATALOG.  THANKS.
    [PLSOPN Operator at GIDNEY has been notified at 14:34:26]
    @INFORMATION MOUNT-REQUESTS /USER
    
    Tape/Disk Mount Queue:
    Volume    Status   Type   Write   Req Name  Req#  Job#  User
    -------  --------  ----  -------  --------  ----  ----  -----
    DBL01    Waiting   Tape  Enabled  LAT        197    65  LATTA
    There is 1 Request in the Queue