lock

Locking an entire VOB disables all write operations to that VOB and forces a database checkpoint by causing a state flush. A typical application is locking a VOB to prevent it from being modified during backup.

You must lock a VOB before backing it up, and you cannot use the -nusers option. With -nusers, it is possible that the VOB will be modified during the backup, and locking with the -nuser option does not perform a database checkpoint.

In general, locking a type object disables these kinds of operations:

• Operations that create, delete, or modify instances of the type
• Operations that delete or modify the type object itself (for example, renaming it)

The following sections describe how these general rules apply to the different kinds of type objects.

• Element type. If an element type is locked, you cannot perform the following operations:
  • Use the type in an rmtype or rename command
  • Create an element of that type with mkelem or mkdir
  • Change an existing element to that type with chtype
  • Modify the element's version tree with checkout, checkin, or mkbranch
• Branch type. If a branch type (as opposed to an instance of a branch type) is locked, you cannot perform the following operations:
  • Use the type in an rmtype, rename, or mkbrtype -replace command
  • Create a branch of that type with mkbranch
  • Rename (that is, change the type of) an existing branch to or from that type with chtype
  • Modify the branch with checkout or checkin
  • Cancel a checkout using uncheckout
  • Attach a label (mklabel) or attribute (mkattr) to a version on an instance of the locked branch type.
  • Remove a label or an attribute from a version on an instance of the locked branch type.

  However, you can perform the following operations because none of them modifies the branch type itself:

  • Create a subbranch at any version on an instance of the locked type.
  • Attach a hyperlink (mkhlink) to a version on an instance of the locked type.
  • Remove a hyperlink (rmhlink) from a version on an instance of the locked type.
• Label type. If a label type is locked, you cannot perform the following operations:
  • Use the type in an rmtype, rename, or mklbtype -replace command
  • Attach or remove a version label of that type with mklabel or rmlabel (This includes moving a label from one version to another with mklabel -replace.)
• Attribute type. If an attribute type is locked, you cannot perform the following operations:
  • Use the type in an rmtype, rename, or mkattype -replace command
  • Attach or remove an attribute of that type with mkattr or rmattr (This includes moving an attribute from one version to another with mkattr -replace.)
• Hyperlink type. If a hyperlink type is locked, you cannot perform the following operations:
  • Use the type in an rmtype, rename, or mkhltype -replace command
  • Create or remove a hyperlink of that type with mkhlink or rmhlink
• Trigger type. If a trigger type is locked, you cannot perform the following operations:
  • Use the type in an rmtype, rename, or mktrtype -replace command
  • (If created with mktrtype -element) Create or remove a trigger of that type with mktrigger or rmtrigger

  In general, locking a trigger type does not inhibit triggers of that type from firing. Exception: Trigger firing is inhibited if a trigger type created with mktrtype -element -all, mktrtype -ucm -all or if mktrtype -type is made obsolete (using lock -obsolete).

If a branch instance is locked, you cannot perform the following operations:

• Rename (that is, change the type of) the branch with chtype
• Modify the branch with checkout or checkin
• Cancel a checkout using uncheckout
• Attach a label to a version on the branch using mklabel
• Remove a label from a version on the branch using rmlabel or mklabel -replace
• Attach an attribute using mkattr
• Remove an attribute using rmattr or mkattr -replace

However, you can perform the following operations because none of them modifies the branch itself:

• Create a subbranch at any version on the branch.
• Attach a hyperlink (mkhlink) to a version on the branch.
• Remove a hyperlink (rmhlink) from a version on the branch.

If a version is locked, you cannot do the following:

• Attach a label using mklabel
• Remove a label using rmlabel or mklabel -replace
• Attach an attribute using mkattr
• Remove an attribute using rmattr or mkattr -replace
• Remove the version using rmver

You must always specify an explicit version to lock or unlock.

Locking a VOB storage pool inhibits commands that create or remove the pool's data containers. It also prevents the pool's scrubbing parameters from being modified with mkpool -update. The following sections describe how this principle applies to the different kinds of storage pools.

• Source pool. If a source storage pool is locked, you cannot perform the following operations:
  • Create an element that would be assigned to that pool, with mkelem or mkdir. (A new element inherits its pool assignments from its parent directory element.)
  • Change an existing element's pool assignment to or from that pool, with chpool.
  • Change an element's element type with chtype, if the change would require recreation of source data containers (for example, changing from type file to type text_file).
  • Check in a new version of an element assigned to that pool.
  • Create or remove a branch of an element assigned to that pool, with mkbranch or rmbranch.
  • Remove a version of an element assigned to that pool, or remove the element itself, with rmver or rmelem.
• Derived object pool. If a derived object storage pool is locked:
  • clearmake cannot winkin a previously unshared derived object in a directory assigned to that pool. (The invocation of promote_server to copy the data container from view-private storage to the derived object storage pool fails.)
  • scrubber cannot remove data containers from the pool.
  • An rmdo command fails for a derived object whose data container is in that pool.
• Cleartext pool. If a cleartext storage pool is locked, an attempt to read a version of an element assigned to that pool may fail. (It fails if a new cleartext data container for that version would have been created and cached in the cleartext pool.)

An object becomes obsolete if it is processed with a lock -obsolete command. An obsolete type object or obsolete storage pool is not only locked, but is also invisible to certain forms of the lstype, lslock, lspool, and lsvtree commands. An obsolete VOB or obsolete VOB object is no different from one with an ordinary lock. You can change an object's status from obsolete to locked by using a lock -replace command:

Similarly, you can use a lock -replace command to make a locked object obsolete.

The unlock command removes a lock from an object, reenabling the previously prohibited operations.

Default

None.

-rep/lace

Uses a single atomic transaction to replace an existing lock with a new lock. (If you use two commands to unlock the object and then lock it again, there is a short interval during which the object is unprotected.)

You can use this option to change a object's status from just locked to obsolete.

Default

Locks an object to all users, but does not make the object obsolete.

-nus/ers login-name [,...]

Allows the specified users to continue using the object, which becomes locked to all other users. The list of user names must be comma-separated, with no white space.

-obs/olete

Locks an object for all users and also makes it obsolete.

Default

Creates one or more event records, with commenting controlled by your .clearcase_profile file (default: -nc). See the comments reference page. Comments can be edited with chevent.

-c/omment comment | -cfi/le comment-file-pname | -cq/uery | -cqe/ach | -nc/omment

Overrides the default with the option you specify. See the comments reference page.

Default

The final arguments are assumed to be the names of elements, branches, or both. To lock another kind of object, you must use an object-selector prefix.

When locking type objects and storage pools, the command processes objects in the VOB containing the current working directory. To lock an entire VOB, you must specify a VOB.

[ -pna/me ] pname ... , object-selector ... (mutually exclusive)

One or more names, specifying the objects to be locked. To lock an element, you can specify the element itself (for example, foo.c@@) or any of its versions (for example, foo.c or foo.c@@/RLS1.3).To lock a branch, use an extended path name (for example, foo.c@@\main\rel2_bugfix). If pname has the form of an object selector, you must use the -pname option to indicate that pname is a path name.

Specify object-selector in one of the following forms:

Table

vob-selector	vob:pname-in-vob pname-in-vob can be the pathname of the VOB tag (whether or not the VOB is mounted) or of any file system object within the VOB (if the VOB is mounted). It cannot be the pathname of the VOB storage directory.
attribute-type-selector	attype:type-name[@vob-selector]
branch-type-selector	brtype:type-name[@vob-selector]
element-type-selector	eltype:type-name[@vob-selector]
hyperlink-type-selector	hltype:type-name[@vob-selector]
label-type-selector	lbtype:type-name[@vob-selector]
trigger-type-selector	trtype:type-name[@vob-selector]
pool-selector	pool:pool-name[@vob-selector]
oid-obj-selector	oid:object-oid[@vob-selector]
policy-selector	policy:policy-name[@vob-selector]
rolemap-selector	rolemap:rolemap-name[@vob-selector]
The following object-selectors apply to the UCM usage model
activity-selector	activity:actvity-name[@vob-selector]
baseline-selector	baseline:baseline-name[@vob-selector]
component-selector	component:component-name[@vob-selector]
folder-selector	folder:folder-name[@vob-selector]
project-selector	project:project-name[@vob-selector]
stream-selector	stream:stream-name[@vob-selector]
Note: In UCM object selectors, @vob-selector refers to a UCM project VOB

-ver/sion version-selector

For each pname, locks the version specified. If pname is not a version-extended name, locks the version selected by the view.