Perforce 2009.2: Command Reference

p4 flush

Synopsis

Update a client workspace's have list without actually copying any files.

Syntax

p4 [g-opts] flush [-n] [file[revRange]...]

Warning

Using p4 flush incorrectly can be dangerous.

If you use p4 flush incorrectly, the server's metadata will not reflect the actual state of your client workspace, and subsequent Perforce commands will not operate on the files you expect! Do not use p4 flush until you fully understand its purpose.

It is rarely necessary to use p4 flush.

Description

p4 flush performs half the work of a p4 sync. Running p4 sync filespec has two effects:

•	The file revisions in the filespec are copied from the depot to the client workspace;

•	The client workspace's have list (which tracks which file revisions have been synced, and is stored on the Perforce server) is updated to reflect the new client workspace contents.

p4 flush performs only the second of these steps. Under most circumstances, this is not desirable, since a client workspace's have list should always reflect the client workspace's true contents. However, if the client workspace's contents are already out of sync with the have list, p4 flush can sometimes be used to bring the have list in sync with the actual contents. Since p4 flush performs no actual file transfers, this command is much faster then the corresponding p4 sync.

Use p4 flush only when you need to update the have list to match the actual state of the client workspace. The Examples subsection describes two such situations.

Options

-n	Display the results of the flush without actually performing the flush. This lets you make sure that the flush does what you think it will do before you do it.
g-opts	See the Global Options section.

Usage Notes

Can File Arguments Use Revision Specifier?	Can File Arguments Use Revision Range?	Minimal Access Level Required
Yes	Yes	read

•

Since p4 flush updates the have list without copying files, and p4 sync -f updates the client workspace to match the have list, p4 flush files followed by p4 sync -f files is almost equivalent to p4 sync files. This means that a bad flush can be almost entirely fixed by following it with a p4 sync -f of the same file revisions that were originally flushed.

Unfortunately, this is not a complete remedy, since any file revisions that were deleted from the have list by p4 flush will remain in the client workspace even after the p4 sync -f. In this case, you will need to manually remove deleted file revisions from the client workspace.

Examples

•	Ten users at the same site need to set up new, identical client workspaces from the same depot at a remote location over a slow link. The standard method calls for each user to run identical p4 sync commands, but since the line speed is slow, there's a faster way:

•	One user runs p4 sync files from his client workspace firstworkspace.

•	The other users copy the newly synced files from the first user's client workspace into their own client workspaces using their local OS file-copying commands.

•	The other users run p4 flush files @firstworkspace, which brings their client workspaces' have lists into sync with the files copied into the client workspaces in the last step.

Since p4 flush moves no files across the slow link, the process can be much faster then running the same p4 sync command ten separate times.

•	Joe has a client workspace called ws that has a Root: of

/usr/joe/project1/subproj

and a View: of

//depot/joe/proj1/subproj/... //joe/...

He decides that all the files under /usr/joe/project1 need to be included in the workspace, and accomplishes this by using p4 client to change the Root: to

/usr/joe/project1

and the View: to

//depot/joe/proj1/... //joe/...

This keeps his current client workspace files in the same place, while extending the scope of the workspace to include other files. But when Joe runs his next p4 sync, he's surprised to see that Perforce deletes every non-open file in the client workspace and replaces it with an identical copy of the same file!

Perforce behaves this way because the have list describes each file's location relative to the client root, and the physical location of each file is only computed when each Perforce command is run. Thus, Perforce thinks that each file has been relocated, and the p4 sync deletes the file from its old location and copies it into its new location.

To make better use of Perforce, Joe might have performed a p4 flush #have instead. This would have updated his client workspace's have list to reflect the files' "new" locations without actually copying any files.

Related Commands

p4 flush is an alias for p4 sync -k	p4 sync -k
To copy files from the depot to the client workspace	p4 sync
To bring the client workspace in sync with the have list after a bad p4 flush	p4 sync -f