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Rockwell Automation 57C650 AutoMax Programming Executive Version 3.8 User Manual

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AutoMax Programming Executive Version 3.x

Lock and Token Handling in VCL

When fetching a system or rack(s) from the VCL, the user will be given the option

of transferring any tokens held by the Version Control Library (VCL) within the

scope of the fetch. If the user chooses to transfer the tokens, the destination copy

will hold the tokens when the fetch is complete. Tokens are not required to fetch.

However, if the user tries to fetch on top of the copy that holds the system or rack

token, he will receive a warning message. The user will be given the option of

continuing the fetch or canceling. If the files being written over have a token

password, the user must enter the password before the files protected by the

token will be written over. If the copy with the token is written over, the resulting

copy will still hold the token. When a token is transferred, the password is nulled

for the destination copy unless the destination originally held the token and had a

password set.
Note that fetching a rack is not considered overwriting the system token because

each rack's files are protected by that rack's token, not the system token. If the

system token is held by the destination copy, and racks are fetched into it, the

user will not receive a message asking whether he wants to overwrite the system

token. However, the user will receive a warning message if the destination holds

the rack token(s).
When fetching from the VCL, locks are taken out in the AutoMax library for the

appropriate system, section(s), rack(s), and task(s). For example, if a user is

fetching a section with two racks, a lock will be taken out in the AutoMax library

for the section. No one else will be able to modify either of the two racks or the

section until the fetch is complete. If a user has selected the Fetch Latest option

for the fetch, a lock is taken out in the VCL so that no one can snapshot anything

during the fetch.
When snapshotting, the VCL cannot already hold the token of any rack or system

group being snapshot. The user will have the option of transferring any tokens

held within the scope of the snapshot. If the token is transferred to the VCL, the

token password is nulled.
When snapshotting to the VCL, locks are taken out in the AutoMax library for the

appropriate system, section(s), rack(s), and task(s). For example, if a user is

snapshotting a system with two racks that belong to the same section, locks will

be taken out in the AutoMax library for the system, section, and the two racks. No

one else will be able to modify the system, section or either of the two racks until

the snapshot is complete. Locks are also taken out in the VCL so that two users

cannot snapshot the same system, section(s), rack(s), or task(s) at the same time.