Merge git://git.kernel.org/pub/scm/gitk/gitk
[git/git.git] / Documentation / everyday.txt
1 Everyday GIT With 20 Commands Or So
2 ===================================
3
4 GIT suite has over 100 commands, and the manual page for each of
5 them discusses what the command does and how it is used in
6 detail, but until you know what command should be used in order
7 to achieve what you want to do, you cannot tell which manual
8 page to look at, and if you know that already you do not need
9 the manual.
10
11 Does that mean you need to know all of them before you can use
12 git? Not at all. Depending on the role you play, the set of
13 commands you need to know is slightly different, but in any case
14 what you need to learn is far smaller than the full set of
15 commands to carry out your day-to-day work. This document is to
16 serve as a cheat-sheet and a set of pointers for people playing
17 various roles.
18
19 <<Basic Repository>> commands are needed by people who has a
20 repository --- that is everybody, because every working tree of
21 git is a repository.
22
23 In addition, <<Individual Developer (Standalone)>> commands are
24 essential for anybody who makes a commit, even for somebody who
25 works alone.
26
27 If you work with other people, you will need commands listed in
28 <<Individual Developer (Participant)>> section as well.
29
30 People who play <<Integrator>> role need to learn some more
31 commands in addition to the above.
32
33 <<Repository Administration>> commands are for system
34 administrators who are responsible to care and feed git
35 repositories to support developers.
36
37
38 Basic Repository[[Basic Repository]]
39 ------------------------------------
40
41 Everybody uses these commands to feed and care git repositories.
42
43 * gitlink:git-init-db[1] or gitlink:git-clone[1] to create a
44 new repository.
45
46 * gitlink:git-fsck-objects[1] to validate the repository.
47
48 * gitlink:git-prune[1] to garbage collect crufts in the
49 repository.
50
51 * gitlink:git-repack[1] to pack loose objects for efficiency.
52
53 Examples
54 ~~~~~~~~
55
56 Check health and remove cruft.::
57 +
58 ------------
59 $ git fsck-objects <1>
60 $ git prune
61 $ git count-objects <2>
62 $ git repack <3>
63 $ git prune <4>
64
65 <1> running without "--full" is usually cheap and assures the
66 repository health reasonably well.
67 <2> check how many loose objects there are and how much
68 diskspace is wasted by not repacking.
69 <3> without "-a" repacks incrementally. repacking every 4-5MB
70 of loose objects accumulation may be a good rule of thumb.
71 <4> after repack, prune removes the duplicate loose objects.
72 ------------
73
74 Repack a small project into single pack.::
75 +
76 ------------
77 $ git repack -a -d <1>
78 $ git prune
79
80 <1> pack all the objects reachable from the refs into one pack
81 and remove unneeded other packs
82 ------------
83
84
85 Individual Developer (Standalone)[[Individual Developer (Standalone)]]
86 ----------------------------------------------------------------------
87
88 A standalone individual developer does not exchange patches with
89 other poeple, and works alone in a single repository, using the
90 following commands.
91
92 * gitlink:git-show-branch[1] to see where you are.
93
94 * gitlink:git-log[1] to see what happened.
95
96 * gitlink:git-whatchanged[1] to find out where things have
97 come from.
98
99 * gitlink:git-checkout[1] and gitlink:git-branch[1] to switch
100 branches.
101
102 * gitlink:git-add[1] and gitlink:git-update-index[1] to manage
103 the index file.
104
105 * gitlink:git-diff[1] and gitlink:git-status[1] to see what
106 you are in the middle of doing.
107
108 * gitlink:git-commit[1] to advance the current branch.
109
110 * gitlink:git-reset[1] and gitlink:git-checkout[1] (with
111 pathname parameters) to undo changes.
112
113 * gitlink:git-pull[1] with "." as the remote to merge between
114 local branches.
115
116 * gitlink:git-rebase[1] to maintain topic branches.
117
118 * gitlink:git-tag[1] to mark known point.
119
120 Examples
121 ~~~~~~~~
122
123 Extract a tarball and create a working tree and a new repository to keep track of it.::
124 +
125 ------------
126 $ tar zxf frotz.tar.gz
127 $ cd frotz
128 $ git-init-db
129 $ git add . <1>
130 $ git commit -m 'import of frotz source tree.'
131 $ git tag v2.43 <2>
132
133 <1> add everything under the current directory.
134 <2> make a lightweight, unannotated tag.
135 ------------
136
137 Create a topic branch and develop.::
138 +
139 ------------
140 $ git checkout -b alsa-audio <1>
141 $ edit/compile/test
142 $ git checkout -- curses/ux_audio_oss.c <2>
143 $ git add curses/ux_audio_alsa.c <3>
144 $ edit/compile/test
145 $ git diff <4>
146 $ git commit -a -s <5>
147 $ edit/compile/test
148 $ git reset --soft HEAD^ <6>
149 $ edit/compile/test
150 $ git diff ORIG_HEAD <7>
151 $ git commit -a -c ORIG_HEAD <8>
152 $ git checkout master <9>
153 $ git pull . alsa-audio <10>
154 $ git log --since='3 days ago' <11>
155 $ git log v2.43.. curses/ <12>
156
157 <1> create a new topic branch.
158 <2> revert your botched changes in "curses/ux_audio_oss.c".
159 <3> you need to tell git if you added a new file; removal and
160 modification will be caught if you do "commit -a" later.
161 <4> to see what changes you are committing.
162 <5> commit everything as you have tested, with your sign-off.
163 <6> take the last commit back, keeping what is in the working tree.
164 <7> look at the changes since the premature commit we took back.
165 <8> redo the commit undone in the previous step, using the message
166 you originally wrote.
167 <9> switch to the master branch.
168 <10> merge a topic branch into your master branch
169 <11> review commit logs; other forms to limit output can be
170 combined and include --max-count=10 (show 10 commits), --until='2005-12-10'.
171 <12> view only the changes that touch what's in curses/
172 directory, since v2.43 tag.
173 ------------
174
175
176 Individual Developer (Participant)[[Individual Developer (Participant)]]
177 ------------------------------------------------------------------------
178
179 A developer working as a participant in a group project needs to
180 learn how to communicate with others, and uses these commands in
181 addition to the ones needed by a standalone developer.
182
183 * gitlink:git-clone[1] from the upstream to prime your local
184 repository.
185
186 * gitlink:git-pull[1] and gitlink:git-fetch[1] from "origin"
187 to keep up-to-date with the upstream.
188
189 * gitlink:git-push[1] to shared repository, if you adopt CVS
190 style shared repository workflow.
191
192 * gitlink:git-format-patch[1] to prepare e-mail submission, if
193 you adopt Linux kernel-style public forum workflow.
194
195 Examples
196 ~~~~~~~~
197
198 Clone the upstream and work on it. Feed changes to upstream.::
199 +
200 ------------
201 $ git clone git://git.kernel.org/pub/scm/.../torvalds/linux-2.6 my2.6
202 $ cd my2.6
203 $ edit/compile/test; git commit -a -s <1>
204 $ git format-patch origin <2>
205 $ git pull <3>
206 $ git whatchanged -p ORIG_HEAD.. arch/i386 include/asm-i386 <4>
207 $ git pull git://git.kernel.org/pub/.../jgarzik/libata-dev.git ALL <5>
208 $ git reset --hard ORIG_HEAD <6>
209 $ git prune <7>
210 $ git fetch --tags <8>
211
212 <1> repeat as needed.
213 <2> extract patches from your branch for e-mail submission.
214 <3> "pull" fetches from "origin" by default and merges into the
215 current branch.
216 <4> immediately after pulling, look at the changes done upstream
217 since last time we checked, only in the
218 area we are interested in.
219 <5> fetch from a specific branch from a specific repository and merge.
220 <6> revert the pull.
221 <7> garbage collect leftover objects from reverted pull.
222 <8> from time to time, obtain official tags from the "origin"
223 and store them under .git/refs/tags/.
224 ------------
225
226
227 Push into another repository.::
228 +
229 ------------
230 satellite$ git clone mothership:frotz/.git frotz <1>
231 satellite$ cd frotz
232 satellite$ cat .git/remotes/origin <2>
233 URL: mothership:frotz/.git
234 Pull: master:origin
235 satellite$ echo 'Push: master:satellite' >>.git/remotes/origin <3>
236 satellite$ edit/compile/test/commit
237 satellite$ git push origin <4>
238
239 mothership$ cd frotz
240 mothership$ git checkout master
241 mothership$ git pull . satellite <5>
242
243 <1> mothership machine has a frotz repository under your home
244 directory; clone from it to start a repository on the satellite
245 machine.
246 <2> clone creates this file by default. It arranges "git pull"
247 to fetch and store the master branch head of mothership machine
248 to local "origin" branch.
249 <3> arrange "git push" to push local "master" branch to
250 "satellite" branch of the mothership machine.
251 <4> push will stash our work away on "satellite" branch on the
252 mothership machine. You could use this as a back-up method.
253 <5> on mothership machine, merge the work done on the satellite
254 machine into the master branch.
255 ------------
256
257 Branch off of a specific tag.::
258 +
259 ------------
260 $ git checkout -b private2.6.14 v2.6.14 <1>
261 $ edit/compile/test; git commit -a
262 $ git checkout master
263 $ git format-patch -k -m --stdout v2.6.14..private2.6.14 |
264 git am -3 -k <2>
265
266 <1> create a private branch based on a well known (but somewhat behind)
267 tag.
268 <2> forward port all changes in private2.6.14 branch to master branch
269 without a formal "merging".
270 ------------
271
272
273 Integrator[[Integrator]]
274 ------------------------
275
276 A fairly central person acting as the integrator in a group
277 project receives changes made by others, reviews and integrates
278 them and publishes the result for others to use, using these
279 commands in addition to the ones needed by participants.
280
281 * gitlink:git-am[1] to apply patches e-mailed in from your
282 contributors.
283
284 * gitlink:git-pull[1] to merge from your trusted lieutenants.
285
286 * gitlink:git-format-patch[1] to prepare and send suggested
287 alternative to contributors.
288
289 * gitlink:git-revert[1] to undo botched commits.
290
291 * gitlink:git-push[1] to publish the bleeding edge.
292
293
294 Examples
295 ~~~~~~~~
296
297 My typical GIT day.::
298 +
299 ------------
300 $ git status <1>
301 $ git show-branch <2>
302 $ mailx <3>
303 & s 2 3 4 5 ./+to-apply
304 & s 7 8 ./+hold-linus
305 & q
306 $ git checkout master
307 $ git am -3 -i -s -u ./+to-apply <4>
308 $ compile/test
309 $ git checkout -b hold/linus && git am -3 -i -s -u ./+hold-linus <5>
310 $ git checkout topic/one && git rebase master <6>
311 $ git checkout pu && git reset --hard master <7>
312 $ git pull . topic/one topic/two && git pull . hold/linus <8>
313 $ git checkout maint
314 $ git cherry-pick master~4 <9>
315 $ compile/test
316 $ git tag -s -m 'GIT 0.99.9x' v0.99.9x <10>
317 $ git fetch ko && git show-branch master maint 'tags/ko-*' <11>
318 $ git push ko <12>
319 $ git push ko v0.99.9x <13>
320
321 <1> see what I was in the middle of doing, if any.
322 <2> see what topic branches I have and think about how ready
323 they are.
324 <3> read mails, save ones that are applicable, and save others
325 that are not quite ready.
326 <4> apply them, interactively, with my sign-offs.
327 <5> create topic branch as needed and apply, again with my
328 sign-offs.
329 <6> rebase internal topic branch that has not been merged to the
330 master, nor exposed as a part of a stable branch.
331 <7> restart "pu" every time from the master.
332 <8> and bundle topic branches still cooking.
333 <9> backport a critical fix.
334 <10> create a signed tag.
335 <11> make sure I did not accidentally rewind master beyond what I
336 already pushed out. "ko" shorthand points at the repository I have
337 at kernel.org, and looks like this:
338 $ cat .git/remotes/ko
339 URL: kernel.org:/pub/scm/git/git.git
340 Pull: master:refs/tags/ko-master
341 Pull: maint:refs/tags/ko-maint
342 Push: master
343 Push: +pu
344 Push: maint
345 In the output from "git show-branch", "master" should have
346 everything "ko-master" has.
347 <12> push out the bleeding edge.
348 <13> push the tag out, too.
349 ------------
350
351
352 Repository Administration[[Repository Administration]]
353 ------------------------------------------------------
354
355 A repository administrator uses the following tools to set up
356 and maintain access to the repository by developers.
357
358 * gitlink:git-daemon[1] to allow anonymous download from
359 repository.
360
361 * gitlink:git-shell[1] can be used as a 'restricted login shell'
362 for shared central repository users.
363
364 link:howto/update-hook-example.txt[update hook howto] has a good
365 example of managing a shared central repository.
366
367
368 Examples
369 ~~~~~~~~
370
371 Run git-daemon to serve /pub/scm from inetd.::
372 +
373 ------------
374 $ grep git /etc/inet.conf
375 git stream tcp nowait nobody \
376 /usr/bin/git-daemon git-daemon --inetd --syslog --export-all /pub/scm
377 ------------
378 +
379 The actual configuration line should be on one line.
380
381 Give push/pull only access to developers.::
382 +
383 ------------
384 $ grep git /etc/passwd <1>
385 alice:x:1000:1000::/home/alice:/usr/bin/git-shell
386 bob:x:1001:1001::/home/bob:/usr/bin/git-shell
387 cindy:x:1002:1002::/home/cindy:/usr/bin/git-shell
388 david:x:1003:1003::/home/david:/usr/bin/git-shell
389 $ grep git /etc/shells <2>
390 /usr/bin/git-shell
391
392 <1> log-in shell is set to /usr/bin/git-shell, which does not
393 allow anything but "git push" and "git pull". The users should
394 get an ssh access to the machine.
395 <2> in many distributions /etc/shells needs to list what is used
396 as the login shell.
397 ------------
398
399 CVS-style shared repository.::
400 +
401 ------------
402 $ grep git /etc/group <1>
403 git:x:9418:alice,bob,cindy,david
404 $ cd /home/devo.git
405 $ ls -l <2>
406 lrwxrwxrwx 1 david git 17 Dec 4 22:40 HEAD -> refs/heads/master
407 drwxrwsr-x 2 david git 4096 Dec 4 22:40 branches
408 -rw-rw-r-- 1 david git 84 Dec 4 22:40 config
409 -rw-rw-r-- 1 david git 58 Dec 4 22:40 description
410 drwxrwsr-x 2 david git 4096 Dec 4 22:40 hooks
411 -rw-rw-r-- 1 david git 37504 Dec 4 22:40 index
412 drwxrwsr-x 2 david git 4096 Dec 4 22:40 info
413 drwxrwsr-x 4 david git 4096 Dec 4 22:40 objects
414 drwxrwsr-x 4 david git 4096 Nov 7 14:58 refs
415 drwxrwsr-x 2 david git 4096 Dec 4 22:40 remotes
416 $ ls -l hooks/update <3>
417 -r-xr-xr-x 1 david git 3536 Dec 4 22:40 update
418 $ cat info/allowed-users <4>
419 refs/heads/master alice\|cindy
420 refs/heads/doc-update bob
421 refs/tags/v[0-9]* david
422
423 <1> place the developers into the same git group.
424 <2> and make the shared repository writable by the group.
425 <3> use update-hook example by Carl from Documentation/howto/
426 for branch policy control.
427 <4> alice and cindy can push into master, only bob can push into doc-update.
428 david is the release manager and is the only person who can
429 create and push version tags.
430 ------------
431
432 HTTP server to support dumb protocol transfer.::
433 +
434 ------------
435 dev$ git update-server-info <1>
436 dev$ ftp user@isp.example.com <2>
437 ftp> cp -r .git /home/user/myproject.git
438
439 <1> make sure your info/refs and objects/info/packs are up-to-date
440 <2> upload to public HTTP server hosted by your ISP.
441 ------------