User Help > Grouping Units of Work in Change Packages > Resync CP Overview > Using the Resync CP Backfill List
  
Using the Resync CP Backfill List
If the change packages you are applying are dependent on other change packages, the Resync CP command presents you with a backfill list that includes all of the required change packages. The following examples illustrate how the backfill list works in the Resync CP command.
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The backfill list is not used when resyncing subproject operations. You must explicitly specify all change packages containing subproject operations that you want to resync or select Implicitly for the Subproject Propagation option.
Using the Backfill List to Include Required Previous Revisions
The following example illustrates a simplified application of the Resync CP command in the main trunk of development for the Aurora project (Aurora_Project.pj).
The project member tool.c includes a bug fix for item 24 and is associated with the file tool.c (revision 1.7) through change package (CP) 24:1.
The developer wants to pick up the changes that address the bug fix and apply these in a Sandbox. In the developer’s Sandbox, tool.c is at revision 1.2.
To apply the bug fix in the Sandbox, the developer uses the si resynccp command to apply CP 24:1 as follows:
si resynccp -S c:/Aurora_Project/project.pj 24:1
Applying change packages...
24:1
The following warnings have occurred:
-------------------

The change package(s)
20:1 -- tool.c(1.3)
21:1 -- tool.c(1.4)
22:1 -- tool.c(1.5)
23:1 -- tool.c(1.6)
are required in order to apply this list of change
packages. They will be automatically added to the list,
since the backfill option is set to Entire Change
Package(cp). --------------------
*** The following set of operations will be performed:
Project: f:/Aurora_Project/project.pj
Sandbox: c:\Aurora_Sandbox\project.pj
Member tool.c: resynchronize to Revision 1.7
Are you sure you wish to proceed? [yn]<n>: y
In this case, the Resync CP command updates the working file revision for tool.c from 1.2 to 1.7 in the Sandbox. This is done by checking out tool.c at 1.7 into the Sandbox. The changes made from revisions 1.3 through 1.6 are already included in this checked out file.
Using the Backfill List to Merge Around Previous Revisions
You can merge around some or all of the required change packages that are presented to you in the backfill list.
The main project, Aurora_Project.pj, now includes an additional bug fix for project member, tool.c. Item 23 addresses that bug fix and is associated with the file tool.c (revision 1.6) through CP 23:1.
The developer wants to pick up the changes that address the bug fix and apply these in a Sandbox. In the developer’s Sandbox, tool.c is at revision 1.2.
Picking up a specific change using the Resync CP command
To pick up the bug fix, the developer uses the si resynccp command in a Sandbox. The developer wants to decide on the specific change packages to include in the operation, so he or she sets the backfill option to Ask to Specify (--backfill=ask). The command runs as follows:
si resynccp -S c:/Aurora_Sandbox/project.pj --backfill=ask 23:1
Applying change packages...
23:1
*** The following list of change packages are used by revisions
before the revision that you require. Each change package is
given, along with the revisions which require them:
20:1 -- tool.c(1.3)
21:1 -- tool.c(1.4)
22:1 -- tool.c(1.5)
Reply with:
y to pick up all these change packages, along with their
associated changes,
s to skip all these revisions and merge around them (default)
c to cancel the command
or a space separated list of change package identifiers from
the list given to be *removed* from the list [y|s|c|#...]?
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When selecting the change packages from the backfill list in the command line interface, you enter the numbers for the change packages you want to exclude from the resync operation; in the GUI, you select the change packages you want to include in the resync operation.
The developer decides to merge around all the intermediate change packages and selects s (skip). The command continues as follows:
The following warnings have occurred:
-------------------
The following members require a merge to be performed:
tool.c
You have not specified a change package, so merged members will
not be locked.
--------------------
*** The following set of operations will be performed:
Project: f:/Aurora_Project/project.pj
Sandbox: c:\Aurora_Sandbox\project.pj
Member tool.c: merge around differences: picking up revisions
1.2 through 1.6, excluding revisions 1.3, 1.4, 1.5, by checking
out Revision 1.2 into the working file, and merging in the
differences between Revision 1.6 and Revision 1.2 with the
differences between Revision 1.5 and Revision 1.3.
Are you sure you wish to proceed? [yn](n): y
If you choose to proceed, you receive a notification listing the updates that have been processed, and any updates that were not processed.
Resync CP updates the working file revision for main.c by checking out revision 1.2 and then merging into the working file the differences between 1.2 and 1.6. The intermediate revisions are not added to the Sandbox because the skip option was selected. Because the resync operation does not use a propagation change package to record the changes, the merged member is not locked.