Managing Files and Changelists

This chapter tells you how to manage files and work in a team development environment, where multiple users who are working on the same files might need to reconcile their changes.

Managing files

To change files in the depot (file repository), you open the files in changelists and submit the changelists with a description of your changes. Perforce assigns numbers to changelists and maintains the revision history of your files. This approach enables you to group related changes and find out who changed a file and why and when it was changed. Here are the basic steps for working with files.



Syncing (retrieving files from the depot)

Issue the p4 sync command, specifying the files and directories you want to retrieve from the depot. You can only sync files that are mapped in your client view.

Adding files to the depot

  1. Create the file in the workspace.

  2. Open the file for add in a changelist (p4 add).

  3. Submit the changelist (p4 submit).

Editing files and checking in changes

  1. If necessary, sync the desired file revision to your workspace (p4 sync).

  2. Open the file for edit in a changelist (p4 edit).

  3. Make your changes.

  4. Submit the changelist (p4 submit). To discard changes, issue the p4 revert command.

Deleting files from the depot

  1. Open the file for delete in a changelist (p4 delete). The file is deleted from your workspace.

  2. Submit the changelist (p4 submit). The file is deleted from the depot.

Discarding changes

Revert the files or the changelist in which the files are open. Reverting has the following effects on open files:

Add: no effect - the file remains in your workspace.

Edit: the revision you opened is resynced from the depot, overwriting any changes you made to the file in your workspace.

Delete: the file is resynced to your workspace.

Files are added to, deleted from, or updated in the depot only when you successfully submit the pending changelist in which the files are open. A changelist can contain a mixture of files open for add, edit and delete.

For details about the syntax that you use to specify files on the command line, refer to Specifying filenames on the command line. The following sections provide more details about working with files.

Syncing (retrieving) files

To retrieve files from the depot into your client workspace, issue the p4 sync command. You cannot sync files that are not in your client view. For details about specifying client views, see Refining workspace views.

Example 15. Copying files from the depot to a client workspace.

The following command retrieves the most recent revisions of all files in the client view from the depot into the workspace. As files are synced, they are listed in the command output.

C:\bruno_ws>p4 sync
//depot/dev/main/bin/bin.linux24x86/readme.txt#1 - added as c:\bruno_ws\dev\main\bin\bin.linux24x86\readme.txt
//depot/dev/main/bin/bin.ntx86/glut32.dll#1 - added as c:\bruno_ws\dev\main\bin\bin.ntx86\glut32.dll
//depot/dev/main/bin/bin.ntx86/jamgraph.exe#2 - added as c:\bruno_ws\dev\main\bin\bin.ntx86\jamgraph.exe

The p4 sync command adds, updates, or deletes files in the client workspace to bring the workspace contents into agreement with the depot. If a file exists within a particular subdirectory in the depot, but that directory does not exist in the client workspace, the directory is created in the client workspace when you sync the file. If a file has been deleted from the depot, p4 sync deletes it from the client workspace.

To sync revisions of files prior to the latest revision in the depot, use revision specifiers. For example, to sync the first revision of Jamfile, which has multiple revisions, issue the following command:

p4 sync //depot/dev/main/jam/Jamfile#1

For more details, refer to Specifying file revisions.

To sync groups of files or entire directories, use wildcards. For example, to sync everything in and below the jam folder, issue the following command:

p4 sync //depot/dev/main/jam/...

For more details, see Perforce wildcards.

The Perforce service tracks which revisions you have synced. For maximum efficiency, Perforce does not resync an already-synced file revision. To resync files you (perhaps inadvertently) deleted manually, specify the -f option when you issue the p4 sync command.

Adding files

To add files to the depot, create the files in your workspace, then issue the p4 add command. The p4 add command opens the files for add in the default pending changelist. The files are added when you successfully submit the default pending changelist. You can open multiple files for add using a single p4 add command by using wildcards. You cannot use the Perforce ... wildcard to add files recursively.

For platform-specific details about adding files recursively (meaning files in subdirectories), see "Adding a Directory Tree" in the Perforce knowledge base:

Example 16. Adding files to a changelist.

Bruno has created a couple of text files that he needs to add to the depot. To add all the text files at once, he uses the "*" wildcard when he issues the p4 add command.

C:\bruno_ws\dev\main\docs\manuals>p4 add *.txt
//depot/dev/main/docs/manuals/installnotes.txt#1 - opened for add
//depot/dev/main/docs/manuals/requirements.txt#1 - opened for add

Now the files he wants to add to the depot are open in his default changelist. The files are stored in the depot when the changelist is submitted.

Example 17. Submitting a changelist to the depot.

Bruno is ready to add his files to the depot. He types p4 submit and sees the following form in a standard text editor:

Change: new
Client: bruno_ws
User:   bruno
Status: new
        <enter description here>
Type:   public
    //depot/dev/main/docs/manuals/installnotes.txt   # add
    //depot/dev/main/docs/manuals/requirements.txt   # add

Bruno changes the contents of the Description: field to describe his file updates. When he's done, he saves the form and exits the editor, and the new files are added to the depot.

You must enter a description in the Description: field. You can delete lines from the Files: field. Any files deleted from this list are moved to the next default changelist, and are listed the next time you submit the default changelist.

If you are adding a file to a directory that does not exist in the depot, the depot directory is created when you successfully submit the changelist.

You can restrict a changelist from public view by changing the Type: field from public to restricted. In general, if a changelist is restricted, only those users with list access to at least one of the files in the changelist are permitted to see the changelist description.

Ignoring groups of files when adding

Sometimes development processes result in the creation of extraneous content that should not be submitted to the depot. Compilers produce object files and executables during development, text editors and word processors produce backup files, and you may have your own personal conventions for notes on work in progress.

To ignore files (or groups of files) when adding, create a file with a list of file specifications you wish to ignore, and set the P4IGNORE environment variable to point to this file.

When you add files, the full local path and parent directories of any file to be added are searched for P4IGNORE files. If any P4IGNORE files exist, their rules are added to a list, with greater precedence given to P4IGNORE rules closest to the file being added.

The syntax for P4IGNORE files is not the same as Perforce syntax. Instead, it is similar to that used by other versioning systems: files are specified in local syntax, a # character at the beginning of a line denotes a comment, a ! character at the beginning of a line excludes the file specification, and the * wildcard matches substrings. The Perforce wildcard of "..." is not permitted.


Meaning in P4IGNORE files


Matches anything except slashes. Matches only within a single directory. Case sensitivity depends on your client platform.


Exclude the file specification from consideration.


Comment character; this line is ignored.

Example 18. Ignoring groups of files when adding.

Bruno unit tests his code before submitting it to the depot and does not want to accidentally add any object files or generated executables when reconciling his workspace.

Bruno first sets P4IGNORE to point to the correct file:

export P4IGNORE=.p4ignore

He then creates the following file and stores it as .p4ignore in the root of his workspace:

# Ignore .p4ignore files
# Ignore object files, shared libraries, executables
# Ignore all text files except readme file

The next time he runs a command (such as p4 add *.*), the rules are applied across the entire workspace.

To override (or ignore) the P4IGNORE file, use the -I option with the p4 add, p4 reconcile, or p4 status commands.

Changing files

To open a file for edit, issue the p4 edit command. When you open a file for edit, Perforce enables write permission for the file in your workspace and adds the file to a changelist. If the file is in the depot but not in your workspace, you must sync it before you open it for edit. You must open a file for edit before you attempt to edit the file.

Example 19. Opening a file for edit.

Bruno wants to make changes to command.c, so he syncs it and opens the file for edit.

p4 sync //depot/dev/command.c
//depot/dev/command.c#8 - added as c:\bruno_ws\dev\command.c

p4 edit //depot/dev/command.c
//depot/dev/command.c#8 - opened for edit

He then edits the file with any text editor. When he's finished, he submits the file to the depot with p4 submit, as described above.

Discarding changes (reverting)

To remove an open file from a changelist and discard any changes you made, issue the p4 revert command. When you revert a file, Perforce restores the last version you synced to your workspace. If you revert a file that is open for add, the file is removed from the changelist but is not deleted from your workspace.

Example 20. Reverting a file

Bruno decides not to add his text files after all.

p4 revert *.txt
//depot/dev/main/docs/manuals/installnotes.txt#none - was add, abandoned
//depot/dev/main/docs/manuals/requirements.txt#none - was add, abandoned

To preview the results of a revert operation without actually reverting files, specify the -n option when you issue the p4 revert command.

Deleting files

To delete files from the depot, you open them for delete by issuing the p4 delete command, then submit the changelist in which they are open. When you delete a file from the depot, previous revisions remain, and a new head revision is added, marked as "deleted." You can still sync previous revisions of the file.

When you issue the p4 delete command, the files are deleted from your workspace but not from the depot. If you revert files that are open for delete, they are restored to your workspace. When you successfully submit the changelist in which they are open, the files are deleted from the depot.

Example 21. Deleting a file from the depot.

Bruno deletes vendor.doc from the depot as follows:

p4 delete //depot/dev/main/docs/manuals/vendor.doc
//depot/dev/main/docs/manuals/vendor.doc#1 - opened for delete

The file is deleted from the client workspace immediately, but it is not deleted from the depot until he issues the p4 submit command.

Managing changelists

To change files in the depot, you open them in a changelist, make any changes to the files, and then submit the changelist. A changelist contains a list of files, their revision numbers, and the operations to be performed on the files. Unsubmitted changelists are referred to as pending changelists.

Submission of changelists is an all-or-nothing operation; that is, either all of the files in the changelist are updated in the depot, or, if an error occurs, none of them are. This approach guarantees that code alterations that affect multiple files occur simultaneously.

Perforce assigns numbers to changelists and also maintains a default changelist, which is numbered when you submit it. You can create multiple changelists to organize your work. For example, one changelist might contain files that are changed to implement a new feature, and another changelist might contain a bug fix. When you open a file, it is placed in the default changelist unless you specify an existing changelist number on the command line using the -c option. For example, to edit a file and submit it in changelist number 4, use p4 edit -c 4 filename. To open a file in the default changelist, omit the -c option.

You can also shelve changelists in order to temporarily preserve work in progress for your own use, or for review by others. Shelving enables you to temporarily cache files in the shared service without formally submitting them to the depot.

The Perforce service might renumber a changelist when you submit it, depending on other users' activities; if your changelist is renumbered, its original number is never reassigned to another changelist.

The commands that add or remove files from changelists are:

  • p4 add

  • p4 delete

  • p4 edit

  • p4 integrate

  • p4 reopen

  • p4 revert

  • p4 shelve

  • p4 unshelve

To submit a numbered changelist, specify the -c option when you issue the p4 submit command. To submit the default changelist, omit the -c option. For details, refer to the p4 submit command description in the P4 Command Reference.

To move files from one changelist to another, issue the p4 reopen -c changenum filenames command, where changenum specifies the number of the target changelist. If you are moving files to the default changelist, use p4 reopen -c default filenames.


Using parallel submits can significantly improve performance. For additional information see the description of the p4 submit command in P4 Command Reference.

Creating numbered changelists

To create a numbered changelist, issue the p4 change command. This command displays the changelist form. Enter a description and make any desired changes; then save the form and exit the editor.

All files open in the default changelist are moved to the new changelist. When you exit the text editor, the changelist is assigned a number. If you delete files from this changelist, the files are moved back to the default changelist.

Example 22. Working with multiple changelists.

Bruno is fixing two different bugs, and needs to submit each fix in a separate changelist. He syncs the head revisions of the files for the first fix and opens the for edit in the default changelist:

C:\bruno_ws\>p4 sync //depot/dev/main/jam/*.c
[list of files synced...]

C:\bruno_ws>p4 edit //depot/dev/main/jam/*.c
[list of files opened for edit...]

Now he issues the p4 change command and enters a description in the changelist form. After he saves the file and exits the editor, Perforce creates a numbered changelist containing the files.

C:\bruno_ws\dev\main\docs\manuals>p4 change

    [Enter description and save form]

Change 777 created with 33 open file(s).

For the second bug fix, he performs the same steps, p4 sync, p4 edit, and p4 change. Now he has two numbered changelists, one for each fix.

The numbers assigned to submitted changelists reflect the order in which the changelists were submitted. When a changelist is submitted, Perforce might renumber it, as shown in the following example.

Example 23. Automatic renumbering of changelists

Bruno has finished fixing the bug that he's been using changelist 777 for. After he created that changelist, he submitted another changelist, and two other users also submitted changelists. Bruno submits changelist 777 with p4 submit -c 777, and sees the following message:

Change 777 renamed change 783 and submitted.

Submitting changelists

To submit a pending changelist, issue the p4 submit command. When you issue the p4 submit command, a form is displayed, listing the files in the changelist. You can remove files from this list. The files you remove remain open in the default pending changelist until you submit them or revert them.

To submit specific files that are open in the default changelist, issue the p4 submit filename command. To specify groups of files, use wildcards. For example, to submit all text files open in the default changelist, type p4 submit "*".txt. (Use quotation marks as an escape code around the * wildcard to prevent it from being interpreted by the local command shell).

After you save the changelist form and exit the text editor, the changelist is submitted to the Perforce service, and the files in the depot are updated. After a changelist has been successfully submitted, only a Perforce administrator can change it, and the only fields that can be changed are the description and user name.

If an error occurs when you submit the default changelist, Perforce creates a numbered changelist containing the files you attempted to submit. You must then fix the problems and submit the numbered changelist using the -c option.

Perforce enables write permission for files that you open for edit and disables write permission when you successfully submit the changelist containing the files. To prevent conflicts with Perforce's management of your workspace, do not change file write permissions manually.

Before committing a changelist, p4 submit briefly locks all files being submitted. If any file cannot be locked or submitted, the files are left open in a numbered pending changelist. By default, the files in a failed submit operation are left locked unless the submit.unlocklocked configurable is set. Files are unlocked even if they were manually locked prior to submit if submit fails when submit.unlocklocked is set.

Deleting changelists

To delete a pending changelist, you must first remove all files and jobs associated with it and then issue the p4 change -d changenum command. Related operations include the following:

  • To move files to another changelist, issue the p4 reopen -c changenum command.

  • To remove files from the changelist and discard any changes, issue the p4 revert -c changenum command.

Changelists that have already been submitted can be deleted only by a Perforce administrator. See the Perforce Server Administrator's Guide: Fundamentals for more information.

Renaming and moving files

To rename or move files, you must first open them for add or edit, and then use the p4 move command:

p4 move source_file target_file

To move groups of files, use matching wildcards in the source_file and target_file specifiers. To move files, you must have Perforce write permission for the specified files. For details about Perforce permissions, see the Perforce Server Administrator's Guide: Fundamentals.

When you rename or move a file using p4 move, the versioning service creates an integration record that links it to its deleted predecessor, preserving the file's history. Integration is also used to create branches and to propagate changes. For details, see Integrating changes.

Shelving work in progress

The Perforce shelving feature enables you to temporarily make copies of your files available to other users without checking the changelist into the depot.

Shelving is useful for individual developers who are switching between tasks or performing cross-platform testing before checking in their changes. Shelving also enables teams to easily hand off changes and to perform code reviews.

Example 24. Shelving a changelist.

Earl has made changes to command.c on a UNIX platform, and now wants others to be able to view and test his changes.

$ p4 edit //depot/dev/command.c
//depot/dev/command.c#9 - opened for edit

$ p4 shelve
Change 123 created with 1 open file(s).
Shelving files for change 123.
edit //depot/dev/command.c#9
Change 123 files shelved.

A pending changelist is created, and the shelved version of command.c is stored in the service. The file command.c remains editable in Earl's workspace, and Earl can continue to work on the file, or can revert his changes and work on something else.

Shelved files remain open in the changelist from which they were shelved. (To add a file to an existing shelved changelist, you must first open that file in that specific changelist.) You can continue to work on the files in your workspace without affecting the shelved files. Shelved files can be synced to other workspaces, including workspaces owned by other users. For example:

Example 25. Unshelving a changelist for code review

Earl has asked for code review and a cross-platform compatibility check on the version of command.c that he shelved in changelist 123. Bruno, who is using a Windows machine, types:

C:\bruno_ws\dev> p4 unshelve -s 123 //depot/dev/command.c
//depot/dev/command.c#9 - unshelved, opened for edit

and conducts the test in the Windows environment while Earl continues on with other work.

When you shelve a file, the version on the shelf is unaffected by commands that you perform in your own workspace, even if you revert the file to work on something else.

Example 26. Handing off files to other users.

Earl's version of command.c works on UNIX, but Bruno's cross-platform check of command.c has revealed a bug. Bruno can take over the work from here, so Earl reverts his workspace and works on something else:

$ p4 revert //depot/dev/command.c
//depot/dev/command.c#9 - was edit, reverted

The shelved version of command.c is still available from Earl's pending changelist 123, and Bruno opens it in a new changelist, changelist 124.

$ p4 unshelve -s 123 -c 124 //depot/dev/command.c
//depot/dev/command.c#9 - unshelved, opened for edit

When Bruno is finished with the work, he can either re-shelve the file (in his own changelist 124, not Earl's changelist 123) for further review, or discard the shelved file and submit the version in his workspace by using p4 submit.

The p4 submit command has a -e option that enables the submitting of shelved files directly from a changelist. All files in the shelved change must be up to date and resolved. Other restrictions can apply in the case of files shelved to stream targets; see the P4 Command Reference for details. (To avoid dealing with these restrictions, you can always move the shelved files into a new pending changelist before submitting that changelist.)

Example 27. Discarding shelved files before submitting a change.

The Windows cross-platform changes are complete, and changelist 124 is ready to be submitted. Bruno uses p4 shelve -d to discard the shelved files.

C:\bruno_ws\dev> p4 shelve -d -c 124
Shelve 124 deleted.

All files in the shelved changelist are deleted. Bruno can now submit the changelist.

C:\bruno_ws\dev> p4 submit -c 124
Change 124 submitted.

Bruno could have shelved the file in changelist 124, and let Earl unshelve it back into his original changelist 123 to complete the check-in.

Displaying information about changelists

To display brief information about changelists, use the p4 changes command. To display full information, use the p4 describe command. The following table describes some useful reporting commands and options.



p4 changes

Displays a list of all pending, submitted, and shelved changelists, one line per changelist, and an abbreviated description.

p4 changes -m count

Limits the number of changelists reported on to the last specified number of changelists.

p4 changes -s status

Limits the list to those changelists with a particular status; for example, p4 changes -s submitted lists only already submitted changelists.

p4 changes -u user

Limits the list to those changelists submitted by a particular user.

p4 changes -c workspace

Limits the list to those changelists submitted from a particular client workspace.

p4 describe changenum

Displays full information about a single changelist. If the changelist has already been submitted, the report includes a list of affected files and the diffs of these files. (You can use the -s option to exclude the file diffs.)

p4 describe -O changenum

If a changelist was renumbered, describe the changelist in terms of its original change number. (For example, the changelist renumbered in the example on Example 23, “Automatic renumbering of changelists” can be retrieved with either p4 describe 783 or p4 describe -O 777.)

For more information, see Changelist reporting.

Diffing files

Perforce provides the ability to diff (compare) revisions of text files. By diffing files, you can display:

  • Changes that you made after opening the file for edit

  • Differences between any two revisions

  • Differences between file revisions in different branches

To diff a file that is synced to your workspace with a depot revision, issue the p4 diff filename#rev command. If you omit the revision specifier, the file in your workspace is compared with the revision you last synced, to display changes you made after syncing it.

To diff two revisions that reside in the depot but not in your workspace, use the p4 diff2 command. To diff a set of files, specify wildcards in the filename argument when you issue the p4 diff2 command.

The p4 diff command performs the comparison on your workstation, but the p4 diff2 command instructs the Perforce service to perform the diff and to send the results to you.

The following table lists some common uses for diff commands.

To diff


Use this command

The workspace file

The head revision

p4 diff file or p4 diff file#head

The workspace file

Revision 3

p4 diff file#3

The head revision

Revision 134

p4 diff2 file file#134

File revision at changelist 32

File revision at changelist 177

p4 diff2 file@32 file@177

The workspace file

A file shelved in pending changelist 123

p4 diff [email protected]=123

All files in release 1

All files in release 2

p4 diff2 //depot/rel1/... //depot/rel2/...

By default, the p4 diff command launches Perforce's internal diff application. To use a different diff program, set the P4DIFF environment variable to specify the path and executable of the desired application. To specify arguments for the external diff application, use the -d option. For details, refer to the P4 Command Reference.

Working offline

The preferred method of working offline (without access to the Perforce service) is to use the Perforce Sandbox. For details, refer to the Perforce Sandbox User's Guide.

If you are not using the Perforce Sandbox, you must manually reconcile your work with the Perforce service when you regain access to it. The following method for working detached assumes that you work on files in your workspace or update the workspace with your additions, changes, and deletions before you update the depot.

To work offline:

  1. Work on files without issuing p4 commands. Instead, use operating system commands to change the permissions on files.

  2. After the network connection is reestablished, use p4 status or p4 reconcile to find all files in your workspace that have changed.

  3. Submit the resulting changelist(s).

To detect changed files, issue the p4 status or p4 reconcile commands. The commands perform essentially the same function, but differ in their default behavior and output format.



p4 reconcile

When called without arguments, p4 reconcile opens the files in a changelist. To preview an operation, you must either use the -n option with p4 reconcile, or use the p4 status command.

p4 status

When called without arguments, p4 status only previews the results of the workspace reconciliation. You must use either p4 status -A (or some combination of the -e, -a, or -d options) to actually open the files in a changelist.