Merge branch 'ld/git-p4-updates'
[git/git.git] / Documentation / git-p4.txt
1 git-p4(1)
2 =========
3
4 NAME
5 ----
6 git-p4 - Import from and submit to Perforce repositories
7
8
9 SYNOPSIS
10 --------
11 [verse]
12 'git p4 clone' [<sync options>] [<clone options>] <p4 depot path>...
13 'git p4 sync' [<sync options>] [<p4 depot path>...]
14 'git p4 rebase'
15 'git p4 submit' [<submit options>] [<master branch name>]
16
17
18 DESCRIPTION
19 -----------
20 This command provides a way to interact with p4 repositories
21 using Git.
22
23 Create a new Git repository from an existing p4 repository using
24 'git p4 clone', giving it one or more p4 depot paths. Incorporate
25 new commits from p4 changes with 'git p4 sync'. The 'sync' command
26 is also used to include new branches from other p4 depot paths.
27 Submit Git changes back to p4 using 'git p4 submit'. The command
28 'git p4 rebase' does a sync plus rebases the current branch onto
29 the updated p4 remote branch.
30
31
32 EXAMPLES
33 --------
34 * Clone a repository:
35 +
36 ------------
37 $ git p4 clone //depot/path/project
38 ------------
39
40 * Do some work in the newly created Git repository:
41 +
42 ------------
43 $ cd project
44 $ vi foo.h
45 $ git commit -a -m "edited foo.h"
46 ------------
47
48 * Update the Git repository with recent changes from p4, rebasing your
49 work on top:
50 +
51 ------------
52 $ git p4 rebase
53 ------------
54
55 * Submit your commits back to p4:
56 +
57 ------------
58 $ git p4 submit
59 ------------
60
61
62 COMMANDS
63 --------
64
65 Clone
66 ~~~~~
67 Generally, 'git p4 clone' is used to create a new Git directory
68 from an existing p4 repository:
69 ------------
70 $ git p4 clone //depot/path/project
71 ------------
72 This:
73
74 1. Creates an empty Git repository in a subdirectory called 'project'.
75 +
76 2. Imports the full contents of the head revision from the given p4
77 depot path into a single commit in the Git branch 'refs/remotes/p4/master'.
78 +
79 3. Creates a local branch, 'master' from this remote and checks it out.
80
81 To reproduce the entire p4 history in Git, use the '@all' modifier on
82 the depot path:
83 ------------
84 $ git p4 clone //depot/path/project@all
85 ------------
86
87
88 Sync
89 ~~~~
90 As development continues in the p4 repository, those changes can
91 be included in the Git repository using:
92 ------------
93 $ git p4 sync
94 ------------
95 This command finds new changes in p4 and imports them as Git commits.
96
97 P4 repositories can be added to an existing Git repository using
98 'git p4 sync' too:
99 ------------
100 $ mkdir repo-git
101 $ cd repo-git
102 $ git init
103 $ git p4 sync //path/in/your/perforce/depot
104 ------------
105 This imports the specified depot into
106 'refs/remotes/p4/master' in an existing Git repository. The
107 `--branch` option can be used to specify a different branch to
108 be used for the p4 content.
109
110 If a Git repository includes branches 'refs/remotes/origin/p4', these
111 will be fetched and consulted first during a 'git p4 sync'. Since
112 importing directly from p4 is considerably slower than pulling changes
113 from a Git remote, this can be useful in a multi-developer environment.
114
115 If there are multiple branches, doing 'git p4 sync' will automatically
116 use the "BRANCH DETECTION" algorithm to try to partition new changes
117 into the right branch. This can be overridden with the `--branch`
118 option to specify just a single branch to update.
119
120
121 Rebase
122 ~~~~~~
123 A common working pattern is to fetch the latest changes from the p4 depot
124 and merge them with local uncommitted changes. Often, the p4 repository
125 is the ultimate location for all code, thus a rebase workflow makes
126 sense. This command does 'git p4 sync' followed by 'git rebase' to move
127 local commits on top of updated p4 changes.
128 ------------
129 $ git p4 rebase
130 ------------
131
132
133 Submit
134 ~~~~~~
135 Submitting changes from a Git repository back to the p4 repository
136 requires a separate p4 client workspace. This should be specified
137 using the `P4CLIENT` environment variable or the Git configuration
138 variable 'git-p4.client'. The p4 client must exist, but the client root
139 will be created and populated if it does not already exist.
140
141 To submit all changes that are in the current Git branch but not in
142 the 'p4/master' branch, use:
143 ------------
144 $ git p4 submit
145 ------------
146
147 To specify a branch other than the current one, use:
148 ------------
149 $ git p4 submit topicbranch
150 ------------
151
152 To specify a single commit or a range of commits, use:
153 ------------
154 $ git p4 submit --commit <sha1>
155 $ git p4 submit --commit <sha1..sha1>
156 ------------
157
158 The upstream reference is generally 'refs/remotes/p4/master', but can
159 be overridden using the `--origin=` command-line option.
160
161 The p4 changes will be created as the user invoking 'git p4 submit'. The
162 `--preserve-user` option will cause ownership to be modified
163 according to the author of the Git commit. This option requires admin
164 privileges in p4, which can be granted using 'p4 protect'.
165
166 To shelve changes instead of submitting, use `--shelve` and `--update-shelve`:
167
168 ----
169 $ git p4 submit --shelve
170 $ git p4 submit --update-shelve 1234 --update-shelve 2345
171 ----
172
173
174 Unshelve
175 ~~~~~~~~
176 Unshelving will take a shelved P4 changelist, and produce the equivalent git commit
177 in the branch refs/remotes/p4/unshelved/<changelist>.
178
179 The git commit is created relative to the current origin revision (HEAD by default).
180 If the shelved changelist's parent revisions differ, git-p4 will refuse to unshelve;
181 you need to be unshelving onto an equivalent tree.
182
183 The origin revision can be changed with the "--origin" option.
184
185 If the target branch in refs/remotes/p4/unshelved already exists, the old one will
186 be renamed.
187
188 ----
189 $ git p4 sync
190 $ git p4 unshelve 12345
191 $ git show refs/remotes/p4/unshelved/12345
192 <submit more changes via p4 to the same files>
193 $ git p4 unshelve 12345
194 <refuses to unshelve until git is in sync with p4 again>
195
196 ----
197
198 OPTIONS
199 -------
200
201 General options
202 ~~~~~~~~~~~~~~~
203 All commands except clone accept these options.
204
205 --git-dir <dir>::
206 Set the `GIT_DIR` environment variable. See linkgit:git[1].
207
208 -v::
209 --verbose::
210 Provide more progress information.
211
212 Sync options
213 ~~~~~~~~~~~~
214 These options can be used in the initial 'clone' as well as in
215 subsequent 'sync' operations.
216
217 --branch <ref>::
218 Import changes into <ref> instead of refs/remotes/p4/master.
219 If <ref> starts with refs/, it is used as is. Otherwise, if
220 it does not start with p4/, that prefix is added.
221 +
222 By default a <ref> not starting with refs/ is treated as the
223 name of a remote-tracking branch (under refs/remotes/). This
224 behavior can be modified using the --import-local option.
225 +
226 The default <ref> is "master".
227 +
228 This example imports a new remote "p4/proj2" into an existing
229 Git repository:
230 +
231 ----
232 $ git init
233 $ git p4 sync --branch=refs/remotes/p4/proj2 //depot/proj2
234 ----
235
236 --detect-branches::
237 Use the branch detection algorithm to find new paths in p4. It is
238 documented below in "BRANCH DETECTION".
239
240 --changesfile <file>::
241 Import exactly the p4 change numbers listed in 'file', one per
242 line. Normally, 'git p4' inspects the current p4 repository
243 state and detects the changes it should import.
244
245 --silent::
246 Do not print any progress information.
247
248 --detect-labels::
249 Query p4 for labels associated with the depot paths, and add
250 them as tags in Git. Limited usefulness as only imports labels
251 associated with new changelists. Deprecated.
252
253 --import-labels::
254 Import labels from p4 into Git.
255
256 --import-local::
257 By default, p4 branches are stored in 'refs/remotes/p4/',
258 where they will be treated as remote-tracking branches by
259 linkgit:git-branch[1] and other commands. This option instead
260 puts p4 branches in 'refs/heads/p4/'. Note that future
261 sync operations must specify `--import-local` as well so that
262 they can find the p4 branches in refs/heads.
263
264 --max-changes <n>::
265 Import at most 'n' changes, rather than the entire range of
266 changes included in the given revision specifier. A typical
267 usage would be use '@all' as the revision specifier, but then
268 to use '--max-changes 1000' to import only the last 1000
269 revisions rather than the entire revision history.
270
271 --changes-block-size <n>::
272 The internal block size to use when converting a revision
273 specifier such as '@all' into a list of specific change
274 numbers. Instead of using a single call to 'p4 changes' to
275 find the full list of changes for the conversion, there are a
276 sequence of calls to 'p4 changes -m', each of which requests
277 one block of changes of the given size. The default block size
278 is 500, which should usually be suitable.
279
280 --keep-path::
281 The mapping of file names from the p4 depot path to Git, by
282 default, involves removing the entire depot path. With this
283 option, the full p4 depot path is retained in Git. For example,
284 path '//depot/main/foo/bar.c', when imported from
285 '//depot/main/', becomes 'foo/bar.c'. With `--keep-path`, the
286 Git path is instead 'depot/main/foo/bar.c'.
287
288 --use-client-spec::
289 Use a client spec to find the list of interesting files in p4.
290 See the "CLIENT SPEC" section below.
291
292 -/ <path>::
293 Exclude selected depot paths when cloning or syncing.
294
295 Clone options
296 ~~~~~~~~~~~~~
297 These options can be used in an initial 'clone', along with the 'sync'
298 options described above.
299
300 --destination <directory>::
301 Where to create the Git repository. If not provided, the last
302 component in the p4 depot path is used to create a new
303 directory.
304
305 --bare::
306 Perform a bare clone. See linkgit:git-clone[1].
307
308 Submit options
309 ~~~~~~~~~~~~~~
310 These options can be used to modify 'git p4 submit' behavior.
311
312 --origin <commit>::
313 Upstream location from which commits are identified to submit to
314 p4. By default, this is the most recent p4 commit reachable
315 from `HEAD`.
316
317 -M::
318 Detect renames. See linkgit:git-diff[1]. Renames will be
319 represented in p4 using explicit 'move' operations. There
320 is no corresponding option to detect copies, but there are
321 variables for both moves and copies.
322
323 --preserve-user::
324 Re-author p4 changes before submitting to p4. This option
325 requires p4 admin privileges.
326
327 --export-labels::
328 Export tags from Git as p4 labels. Tags found in Git are applied
329 to the perforce working directory.
330
331 -n::
332 --dry-run::
333 Show just what commits would be submitted to p4; do not change
334 state in Git or p4.
335
336 --prepare-p4-only::
337 Apply a commit to the p4 workspace, opening, adding and deleting
338 files in p4 as for a normal submit operation. Do not issue the
339 final "p4 submit", but instead print a message about how to
340 submit manually or revert. This option always stops after the
341 first (oldest) commit. Git tags are not exported to p4.
342
343 --shelve::
344 Instead of submitting create a series of shelved changelists.
345 After creating each shelve, the relevant files are reverted/deleted.
346 If you have multiple commits pending multiple shelves will be created.
347
348 --update-shelve CHANGELIST::
349 Update an existing shelved changelist with this commit. Implies
350 --shelve. Repeat for multiple shelved changelists.
351
352 --conflict=(ask|skip|quit)::
353 Conflicts can occur when applying a commit to p4. When this
354 happens, the default behavior ("ask") is to prompt whether to
355 skip this commit and continue, or quit. This option can be used
356 to bypass the prompt, causing conflicting commits to be automatically
357 skipped, or to quit trying to apply commits, without prompting.
358
359 --branch <branch>::
360 After submitting, sync this named branch instead of the default
361 p4/master. See the "Sync options" section above for more
362 information.
363
364 --commit <sha1>|<sha1..sha1>::
365 Submit only the specified commit or range of commits, instead of the full
366 list of changes that are in the current Git branch.
367
368 --disable-rebase::
369 Disable the automatic rebase after all commits have been successfully
370 submitted. Can also be set with git-p4.disableRebase.
371
372 --disable-p4sync::
373 Disable the automatic sync of p4/master from Perforce after commits have
374 been submitted. Implies --disable-rebase. Can also be set with
375 git-p4.disableP4Sync. Sync with origin/master still goes ahead if possible.
376
377 Rebase options
378 ~~~~~~~~~~~~~~
379 These options can be used to modify 'git p4 rebase' behavior.
380
381 --import-labels::
382 Import p4 labels.
383
384 Unshelve options
385 ~~~~~~~~~~~~~~~~
386
387 --origin::
388 Sets the git refspec against which the shelved P4 changelist is compared.
389 Defaults to p4/master.
390
391 DEPOT PATH SYNTAX
392 -----------------
393 The p4 depot path argument to 'git p4 sync' and 'git p4 clone' can
394 be one or more space-separated p4 depot paths, with an optional
395 p4 revision specifier on the end:
396
397 "//depot/my/project"::
398 Import one commit with all files in the '#head' change under that tree.
399
400 "//depot/my/project@all"::
401 Import one commit for each change in the history of that depot path.
402
403 "//depot/my/project@1,6"::
404 Import only changes 1 through 6.
405
406 "//depot/proj1@all //depot/proj2@all"::
407 Import all changes from both named depot paths into a single
408 repository. Only files below these directories are included.
409 There is not a subdirectory in Git for each "proj1" and "proj2".
410 You must use the `--destination` option when specifying more
411 than one depot path. The revision specifier must be specified
412 identically on each depot path. If there are files in the
413 depot paths with the same name, the path with the most recently
414 updated version of the file is the one that appears in Git.
415
416 See 'p4 help revisions' for the full syntax of p4 revision specifiers.
417
418
419 CLIENT SPEC
420 -----------
421 The p4 client specification is maintained with the 'p4 client' command
422 and contains among other fields, a View that specifies how the depot
423 is mapped into the client repository. The 'clone' and 'sync' commands
424 can consult the client spec when given the `--use-client-spec` option or
425 when the useClientSpec variable is true. After 'git p4 clone', the
426 useClientSpec variable is automatically set in the repository
427 configuration file. This allows future 'git p4 submit' commands to
428 work properly; the submit command looks only at the variable and does
429 not have a command-line option.
430
431 The full syntax for a p4 view is documented in 'p4 help views'. 'git p4'
432 knows only a subset of the view syntax. It understands multi-line
433 mappings, overlays with '+', exclusions with '-' and double-quotes
434 around whitespace. Of the possible wildcards, 'git p4' only handles
435 '...', and only when it is at the end of the path. 'git p4' will complain
436 if it encounters an unhandled wildcard.
437
438 Bugs in the implementation of overlap mappings exist. If multiple depot
439 paths map through overlays to the same location in the repository,
440 'git p4' can choose the wrong one. This is hard to solve without
441 dedicating a client spec just for 'git p4'.
442
443 The name of the client can be given to 'git p4' in multiple ways. The
444 variable 'git-p4.client' takes precedence if it exists. Otherwise,
445 normal p4 mechanisms of determining the client are used: environment
446 variable `P4CLIENT`, a file referenced by `P4CONFIG`, or the local host name.
447
448
449 BRANCH DETECTION
450 ----------------
451 P4 does not have the same concept of a branch as Git. Instead,
452 p4 organizes its content as a directory tree, where by convention
453 different logical branches are in different locations in the tree.
454 The 'p4 branch' command is used to maintain mappings between
455 different areas in the tree, and indicate related content. 'git p4'
456 can use these mappings to determine branch relationships.
457
458 If you have a repository where all the branches of interest exist as
459 subdirectories of a single depot path, you can use `--detect-branches`
460 when cloning or syncing to have 'git p4' automatically find
461 subdirectories in p4, and to generate these as branches in Git.
462
463 For example, if the P4 repository structure is:
464 ----
465 //depot/main/...
466 //depot/branch1/...
467 ----
468
469 And "p4 branch -o branch1" shows a View line that looks like:
470 ----
471 //depot/main/... //depot/branch1/...
472 ----
473
474 Then this 'git p4 clone' command:
475 ----
476 git p4 clone --detect-branches //depot@all
477 ----
478 produces a separate branch in 'refs/remotes/p4/' for //depot/main,
479 called 'master', and one for //depot/branch1 called 'depot/branch1'.
480
481 However, it is not necessary to create branches in p4 to be able to use
482 them like branches. Because it is difficult to infer branch
483 relationships automatically, a Git configuration setting
484 'git-p4.branchList' can be used to explicitly identify branch
485 relationships. It is a list of "source:destination" pairs, like a
486 simple p4 branch specification, where the "source" and "destination" are
487 the path elements in the p4 repository. The example above relied on the
488 presence of the p4 branch. Without p4 branches, the same result will
489 occur with:
490 ----
491 git init depot
492 cd depot
493 git config git-p4.branchList main:branch1
494 git p4 clone --detect-branches //depot@all .
495 ----
496
497
498 PERFORMANCE
499 -----------
500 The fast-import mechanism used by 'git p4' creates one pack file for
501 each invocation of 'git p4 sync'. Normally, Git garbage compression
502 (linkgit:git-gc[1]) automatically compresses these to fewer pack files,
503 but explicit invocation of 'git repack -adf' may improve performance.
504
505
506 CONFIGURATION VARIABLES
507 -----------------------
508 The following config settings can be used to modify 'git p4' behavior.
509 They all are in the 'git-p4' section.
510
511 General variables
512 ~~~~~~~~~~~~~~~~~
513 git-p4.user::
514 User specified as an option to all p4 commands, with '-u <user>'.
515 The environment variable `P4USER` can be used instead.
516
517 git-p4.password::
518 Password specified as an option to all p4 commands, with
519 '-P <password>'.
520 The environment variable `P4PASS` can be used instead.
521
522 git-p4.port::
523 Port specified as an option to all p4 commands, with
524 '-p <port>'.
525 The environment variable `P4PORT` can be used instead.
526
527 git-p4.host::
528 Host specified as an option to all p4 commands, with
529 '-h <host>'.
530 The environment variable `P4HOST` can be used instead.
531
532 git-p4.client::
533 Client specified as an option to all p4 commands, with
534 '-c <client>', including the client spec.
535
536 git-p4.retries::
537 Specifies the number of times to retry a p4 command (notably,
538 'p4 sync') if the network times out. The default value is 3.
539 Set the value to 0 to disable retries or if your p4 version
540 does not support retries (pre 2012.2).
541
542 Clone and sync variables
543 ~~~~~~~~~~~~~~~~~~~~~~~~
544 git-p4.syncFromOrigin::
545 Because importing commits from other Git repositories is much faster
546 than importing them from p4, a mechanism exists to find p4 changes
547 first in Git remotes. If branches exist under 'refs/remote/origin/p4',
548 those will be fetched and used when syncing from p4. This
549 variable can be set to 'false' to disable this behavior.
550
551 git-p4.branchUser::
552 One phase in branch detection involves looking at p4 branches
553 to find new ones to import. By default, all branches are
554 inspected. This option limits the search to just those owned
555 by the single user named in the variable.
556
557 git-p4.branchList::
558 List of branches to be imported when branch detection is
559 enabled. Each entry should be a pair of branch names separated
560 by a colon (:). This example declares that both branchA and
561 branchB were created from main:
562 +
563 -------------
564 git config git-p4.branchList main:branchA
565 git config --add git-p4.branchList main:branchB
566 -------------
567
568 git-p4.ignoredP4Labels::
569 List of p4 labels to ignore. This is built automatically as
570 unimportable labels are discovered.
571
572 git-p4.importLabels::
573 Import p4 labels into git, as per --import-labels.
574
575 git-p4.labelImportRegexp::
576 Only p4 labels matching this regular expression will be imported. The
577 default value is '[a-zA-Z0-9_\-.]+$'.
578
579 git-p4.useClientSpec::
580 Specify that the p4 client spec should be used to identify p4
581 depot paths of interest. This is equivalent to specifying the
582 option `--use-client-spec`. See the "CLIENT SPEC" section above.
583 This variable is a boolean, not the name of a p4 client.
584
585 git-p4.pathEncoding::
586 Perforce keeps the encoding of a path as given by the originating OS.
587 Git expects paths encoded as UTF-8. Use this config to tell git-p4
588 what encoding Perforce had used for the paths. This encoding is used
589 to transcode the paths to UTF-8. As an example, Perforce on Windows
590 often uses "cp1252" to encode path names.
591
592 git-p4.largeFileSystem::
593 Specify the system that is used for large (binary) files. Please note
594 that large file systems do not support the 'git p4 submit' command.
595 Only Git LFS is implemented right now (see https://git-lfs.github.com/
596 for more information). Download and install the Git LFS command line
597 extension to use this option and configure it like this:
598 +
599 -------------
600 git config git-p4.largeFileSystem GitLFS
601 -------------
602
603 git-p4.largeFileExtensions::
604 All files matching a file extension in the list will be processed
605 by the large file system. Do not prefix the extensions with '.'.
606
607 git-p4.largeFileThreshold::
608 All files with an uncompressed size exceeding the threshold will be
609 processed by the large file system. By default the threshold is
610 defined in bytes. Add the suffix k, m, or g to change the unit.
611
612 git-p4.largeFileCompressedThreshold::
613 All files with a compressed size exceeding the threshold will be
614 processed by the large file system. This option might slow down
615 your clone/sync process. By default the threshold is defined in
616 bytes. Add the suffix k, m, or g to change the unit.
617
618 git-p4.largeFilePush::
619 Boolean variable which defines if large files are automatically
620 pushed to a server.
621
622 git-p4.keepEmptyCommits::
623 A changelist that contains only excluded files will be imported
624 as an empty commit if this boolean option is set to true.
625
626 git-p4.mapUser::
627 Map a P4 user to a name and email address in Git. Use a string
628 with the following format to create a mapping:
629 +
630 -------------
631 git config --add git-p4.mapUser "p4user = First Last <mail@address.com>"
632 -------------
633 +
634 A mapping will override any user information from P4. Mappings for
635 multiple P4 user can be defined.
636
637 Submit variables
638 ~~~~~~~~~~~~~~~~
639 git-p4.detectRenames::
640 Detect renames. See linkgit:git-diff[1]. This can be true,
641 false, or a score as expected by 'git diff -M'.
642
643 git-p4.detectCopies::
644 Detect copies. See linkgit:git-diff[1]. This can be true,
645 false, or a score as expected by 'git diff -C'.
646
647 git-p4.detectCopiesHarder::
648 Detect copies harder. See linkgit:git-diff[1]. A boolean.
649
650 git-p4.preserveUser::
651 On submit, re-author changes to reflect the Git author,
652 regardless of who invokes 'git p4 submit'.
653
654 git-p4.allowMissingP4Users::
655 When 'preserveUser' is true, 'git p4' normally dies if it
656 cannot find an author in the p4 user map. This setting
657 submits the change regardless.
658
659 git-p4.skipSubmitEdit::
660 The submit process invokes the editor before each p4 change
661 is submitted. If this setting is true, though, the editing
662 step is skipped.
663
664 git-p4.skipSubmitEditCheck::
665 After editing the p4 change message, 'git p4' makes sure that
666 the description really was changed by looking at the file
667 modification time. This option disables that test.
668
669 git-p4.allowSubmit::
670 By default, any branch can be used as the source for a 'git p4
671 submit' operation. This configuration variable, if set, permits only
672 the named branches to be used as submit sources. Branch names
673 must be the short names (no "refs/heads/"), and should be
674 separated by commas (","), with no spaces.
675
676 git-p4.skipUserNameCheck::
677 If the user running 'git p4 submit' does not exist in the p4
678 user map, 'git p4' exits. This option can be used to force
679 submission regardless.
680
681 git-p4.attemptRCSCleanup::
682 If enabled, 'git p4 submit' will attempt to cleanup RCS keywords
683 ($Header$, etc). These would otherwise cause merge conflicts and prevent
684 the submit going ahead. This option should be considered experimental at
685 present.
686
687 git-p4.exportLabels::
688 Export Git tags to p4 labels, as per --export-labels.
689
690 git-p4.labelExportRegexp::
691 Only p4 labels matching this regular expression will be exported. The
692 default value is '[a-zA-Z0-9_\-.]+$'.
693
694 git-p4.conflict::
695 Specify submit behavior when a conflict with p4 is found, as per
696 --conflict. The default behavior is 'ask'.
697
698 git-p4.disableRebase::
699 Do not rebase the tree against p4/master following a submit.
700
701 git-p4.disableP4Sync::
702 Do not sync p4/master with Perforce following a submit. Implies git-p4.disableRebase.
703
704 IMPLEMENTATION DETAILS
705 ----------------------
706 * Changesets from p4 are imported using Git fast-import.
707 * Cloning or syncing does not require a p4 client; file contents are
708 collected using 'p4 print'.
709 * Submitting requires a p4 client, which is not in the same location
710 as the Git repository. Patches are applied, one at a time, to
711 this p4 client and submitted from there.
712 * Each commit imported by 'git p4' has a line at the end of the log
713 message indicating the p4 depot location and change number. This
714 line is used by later 'git p4 sync' operations to know which p4
715 changes are new.