This file contains reference information for the core git commands. It is actually based on the source from Petr Baudis' tree and may therefore contain a few 'extras' that may or may not make it upstream. The README contains much useful definition and clarification info - read that first. And of the commands, I suggest reading 'update-cache' and 'read-tree' first - I wish I had! Thanks to original email authors and proof readers esp Junio C Hamano David Greaves 24/4/05 Identifier terminology used: Indicates any object sha1 identifier Indicates a blob object sha1 identifier Indicates a tree object sha1 identifier Indicates a commit object sha1 identifier Indicates a tree or commit object sha1 identifier (usually because the command can read the a contains). [Eventually may be replaced with if means in all commands] Indicates that an object type is required. Currently one of: blob/tree/commit Indicates a filename - often includes leading path Indicates the path of a file (is this ever useful?) ################################################################ cat-file cat-file (-t | ) Provide contents or type of objects in the repository. The type is required if -t is not being used to find the object type. The sha1 identifier of the object. -t show the object type identified by One of: blob/tree/commit Output If -t is specified, one of: blob/tree/commit Otherwise the raw (though uncompressed) contents of the will be returned. ################################################################ check-files check-files ... Check that a list of files are up-to-date between the filesystem and the cache. Used to verify a patch target before doing a patch. Files that do not exist on the filesystem are considered up-to-date (whether or not they are in the cache). Emits an error message on failure. preparing to update existing file not in cache exists but is not in the cache preparing to update file not uptodate in cache on disk is not up-to-date with the cache exits with a status code indicating success if all files are up-to-date. see also: update-cache ################################################################ checkout-cache checkout-cache [-q] [-a] [-f] [-n] [--prefix=] [--] ... Will copy all files listed from the cache to the working directory (not overwriting existing files). Note that the file contents are restored - NOT the file permissions. ??? l 58 checkout-cache.c says restore executable bit. -q be quiet if files exist or are not in the cache -f forces overwrite of existing files -a checks out all files in the cache (will then continue to process listed files). -n Don't checkout new files, only refresh files already checked out. --prefix= When creating files, prepend (usually a directory including a trailing /) -- Do not interpret any more arguments as options. Note that the order of the flags matters: checkout-cache -a -f file.c will first check out all files listed in the cache (but not overwrite any old ones), and then force-checkout file.c a second time (ie that one _will_ overwrite any old contents with the same filename). Also, just doing "checkout-cache" does nothing. You probably meant "checkout-cache -a". And if you want to force it, you want "checkout-cache -f -a". Intuitiveness is not the goal here. Repeatability is. The reason for the "no arguments means no work" thing is that from scripts you are supposed to be able to do things like find . -name '*.h' -print0 | xargs -0 checkout-cache -f -- which will force all existing *.h files to be replaced with their cached copies. If an empty command line implied "all", then this would force-refresh everything in the cache, which was not the point. To update and refresh only the files already checked out: checkout-cache -n -f -a && update-cache --ignore-missing --refresh Oh, and the "--" is just a good idea when you know the rest will be filenames. Just so that you wouldn't have a filename of "-a" causing problems (not possible in the above example, but get used to it in scripting!). The prefix ability basically makes it trivial to use checkout-cache as a "export as tree" function. Just read the desired tree into the index, and do a checkout-cache --prefix=export-dir/ -a and checkout-cache will "export" the cache into the specified directory. NOTE! The final "/" is important. The exported name is literally just prefixed with the specified string, so you can also do something like checkout-cache --prefix=.merged- Makefile to check out the currently cached copy of "Makefile" into the file ".merged-Makefile". ################################################################ commit-tree commit-tree [-p ]* < changelog Creates a new commit object based on the provided tree object and emits the new commit object id on stdout. If no parent is given then it is considered to be an initial tree. A commit object usually has 1 parent (a commit after a change) or up to 16 parents. More than one parent represents a merge of branches that led to them. While a tree represents a particular directory state of a working directory, a commit represents that state in "time", and explains how to get there. Normally a commit would identify a new "HEAD" state, and while git doesn't care where you save the note about that state, in practice we tend to just write the result to the file ".git/HEAD", so that we can always see what the last committed state was. Options An existing tree object -p Each -p indicates a the id of a parent commit object. Commit Information A commit encapsulates: all parent object ids author name, email and date committer name and email and the commit time. If not provided, commit-tree uses your name, hostname and domain to provide author and committer info. This can be overridden using the following environment variables. AUTHOR_NAME AUTHOR_EMAIL AUTHOR_DATE COMMIT_AUTHOR_NAME COMMIT_AUTHOR_EMAIL (nb <,> and '\n's are stripped) A commit comment is read from stdin (max 999 chars). If a changelog entry is not provided via '<' redirection, commit-tree will just wait for one to be entered and terminated with ^D see also: write-tree ################################################################ diff-cache diff-cache [-p] [-r] [-z] [--cached] Compares the content and mode of the blobs found via a tree object with the content of the current cache and, optionally ignoring the stat state of the file on disk. The id of a tree or commit object to diff against. -p generate patch (see section on generating patches) -r recurse -z \0 line termination on output --cached do not consider the on-disk file at all Output format: See "Output format from diff-cache, diff-tree and show-diff" section. Operating Modes You can choose whether you want to trust the index file entirely (using the "--cached" flag) or ask the diff logic to show any files that don't match the stat state as being "tentatively changed". Both of these operations are very useful indeed. Cached Mode If --cached is specified, it allows you to ask: show me the differences between HEAD and the current index contents (the ones I'd write with a "write-tree") For example, let's say that you have worked on your index file, and are ready to commit. You want to see eactly _what_ you are going to commit is without having to write a new tree object and compare it that way, and to do that, you just do diff-cache --cached $(cat .git/HEAD) Example: let's say I had renamed "commit.c" to "git-commit.c", and I had done an "upate-cache" to make that effective in the index file. "show-diff" wouldn't show anything at all, since the index file matches my working directory. But doing a diff-cache does: torvalds@ppc970:~/git> diff-cache --cached $(cat .git/HEAD) -100644 blob 4161aecc6700a2eb579e842af0b7f22b98443f74 commit.c +100644 blob 4161aecc6700a2eb579e842af0b7f22b98443f74 git-commit.c And as you can see, the output matches "diff-tree -r" output (we always do equivalent of "-r", since the index is flat). You can trivially see that the above is a rename. In fact, "diff-cache --cached" _should_ always be entirely equivalent to actually doing a "write-tree" and comparing that. Except this one is much nicer for the case where you just want to check where you are. So doing a "diff-cache --cached" is basically very useful when you are asking yourself "what have I already marked for being committed, and what's the difference to a previous tree". Non-cached Mode The "non-cached" mode takes a different approach, and is potentially the even more useful of the two in that what it does can't be emulated with a "write-tree + diff-tree". Thus that's the default mode. The non-cached version asks the question "show me the differences between HEAD and the currently checked out tree - index contents _and_ files that aren't up-to-date" which is obviously a very useful question too, since that tells you what you _could_ commit. Again, the output matches the "diff-tree -r" output to a tee, but with a twist. The twist is that if some file doesn't match the cache, we don't have a backing store thing for it, and we use the magic "all-zero" sha1 to show that. So let's say that you have edited "kernel/sched.c", but have not actually done an update-cache on it yet - there is no "object" associated with the new state, and you get: torvalds@ppc970:~/v2.6/linux> diff-cache $(cat .git/HEAD ) *100644->100664 blob 7476bbcfe5ef5a1dd87d745f298b831143e4d77e->0000000000000000000000000000000000000000 kernel/sched.c ie it shows that the tree has changed, and that "kernel/sched.c" has is not up-to-date and may contain new stuff. The all-zero sha1 means that to get the real diff, you need to look at the object in the working directory directly rather than do an object-to-object diff. NOTE! As with other commands of this type, "diff-cache" does not actually look at the contents of the file at all. So maybe "kernel/sched.c" hasn't actually changed, and it's just that you touched it. In either case, it's a note that you need to upate-cache it to make the cache be in sync. NOTE 2! You can have a mixture of files show up as "has been updated" and "is still dirty in the working directory" together. You can always tell which file is in which state, since the "has been updated" ones show a valid sha1, and the "not in sync with the index" ones will always have the special all-zero sha1. ################################################################ diff-tree diff-tree [-p] [-r] [-z] []* Compares the content and mode of the blobs found via two tree objects. Note that diff-tree can use the tree encapsulated in a commit object. The id of a tree or commit object. If provided, the results are limited to a subset of files matching one of these prefix strings. ie file matches /^||.../ Note that pattern does not provide any wildcard or regexp features. -p generate patch (see section on generating patches) -r recurse -z \0 line termination on output Limiting Output If you're only interested in differences in a subset of files, for example some architecture-specific files, you might do: diff-tree -r arch/ia64 include/asm-ia64 and it will only show you what changed in those two directories. Or if you are searching for what changed in just kernel/sched.c, just do diff-tree -r kernel/sched.c and it will ignore all differences to other files. The pattern is always the prefix, and is matched exactly (ie there are no wildcards - although matching a directory, which it does support, can obviously be seen as a "wildcard" for all the files under that directory). Output format: See "Output format from diff-cache, diff-tree and show-diff" section. An example of normal usage is: torvalds@ppc970:~/git> diff-tree 5319e4d609cdd282069cc4dce33c1db559539b03 b4e628ea30d5ab3606119d2ea5caeab141d38df7 *100664->100664 blob ac348b7d5278e9d04e3a1cd417389379c32b014f->a01513ed4d4d565911a60981bfb4173311ba3688 fsck-cache.c which tells you that the last commit changed just one file (it's from this one: commit 3c6f7ca19ad4043e9e72fa94106f352897e651a8 tree 5319e4d609cdd282069cc4dce33c1db559539b03 parent b4e628ea30d5ab3606119d2ea5caeab141d38df7 author Linus Torvalds Sat Apr 9 12:02:30 2005 committer Linus Torvalds Sat Apr 9 12:02:30 2005 Make "fsck-cache" print out all the root commits it finds. Once I do the reference tracking, I'll also make it print out all the HEAD commits it finds, which is even more interesting. in case you care). ################################################################ diff-tree-helper diff-tree-helper [-z] Reads output from diff-cache, diff-tree and show-diff and generates patch format output. -z \0 line termination on input See also the section on generating patches. ################################################################ fsck-cache fsck-cache [[--unreachable] *] Verifies the connectivity and validity of the objects in the database. A commit object to treat as the head of an unreachability trace --unreachable print out objects that exist but that aren't readable from any of the specified root nodes It tests SHA1 and general object sanity, but it does full tracking of the resulting reachability and everything else. It prints out any corruption it finds (missing or bad objects), and if you use the "--unreachable" flag it will also print out objects that exist but that aren't readable from any of the specified root nodes. So for example fsck-cache --unreachable $(cat .git/HEAD) or, for Cogito users: fsck-cache --unreachable $(cat .git/heads/*) will do quite a _lot_ of verification on the tree. There are a few extra validity tests to be added (make sure that tree objects are sorted properly etc), but on the whole if "fsck-cache" is happy, you do have a valid tree. Any corrupt objects you will have to find in backups or other archives (ie you can just remove them and do an "rsync" with some other site in the hopes that somebody else has the object you have corrupted). Of course, "valid tree" doesn't mean that it wasn't generated by some evil person, and the end result might be crap. Git is a revision tracking system, not a quality assurance system ;) Extracted Diagnostics expect dangling commits - potential heads - due to lack of head information You haven't specified any nodes as heads so it won't be possible to differentiate between un-parented commits and root nodes. missing sha1 directory '' The directory holding the sha1 objects is missing. unreachable The object , isn't actually referred to directly or indirectly in any of the trees or commits seen. This can mean that there's another root na SHA1_ode that you're not specifying or that the tree is corrupt. If you haven't missed a root node then you might as well delete unreachable nodes since they can't be used. missing The object , is referred to but isn't present in the database. dangling The object , is present in the database but never _directly_ used. A dangling commit could be a root node. warning: fsck-cache: tree has full pathnames in it And it shouldn't... sha1 mismatch The database has an object who's sha1 doesn't match the database value. This indicates a ??serious?? data integrity problem. (note: this error occured during early git development when the database format changed.) Environment Variables SHA1_FILE_DIRECTORY used to specify the object database root (usually .git/objects) ################################################################ git-export git-export top [base] probably deprecated: On Wed, 20 Apr 2005, Petr Baudis wrote: >> I will probably not buy git-export, though. (That is, it is merged, but >> I won't make git frontend for it.) My "git export" already does >> something different, but more importantly, "git patch" of mine already >> does effectively the same thing as you do, just for a single patch; so I >> will probably just extend it to do it for an (a,b] range of patches. That's fine. It was a quick hack, just to show that if somebody wants to, the data is trivially exportable. Linus Although in Linus' distribution, git-export is not part of 'core' git. ################################################################ init-db init-db This simply creates an empty git object database - basically a .git directory. If the object storage directory is specified via the SHA1_FILE_DIRECTORY environment variable then the sha1 directories are created underneath - otherwise the default .git/objects directory is used. init-db won't hurt an existing repository. ################################################################ ls-tree ls-tree [-r] [-z] convert the tree object to a human readable (and script processable) form. Id of a tree or commit object. -r recurse into sub-trees -z \0 line termination on output Output Format \t \t \t ################################################################ merge-base merge-base merge-base finds as good a common ancestor as possible. Given a selection of equally good common ancestors it should not be relied on to decide in any particular way. The merge-base algorithm is still in flux - use the source... ################################################################ merge-cache merge-cache (-a | -- | *) This looks up the (s) in the cache and, if there are any merge entries, unpacks all of them (which may be just one file, of course) into up to three separate temporary files, and then executes the supplied with those three files as arguments 1,2,3 (empty argument if no file), and as argument 4. -- Interpret all future arguments as filenames -a Run merge against all files in the cache that need merging. If merge-cache is called with multiple s (or -a) then it processes them in turn only stopping if merge returns a non-zero exit code. Typically this is run with the a script calling the merge command from the RCS package. A sample script called git-merge-one-file-script is included in the ditribution. ALERT ALERT ALERT! The git "merge object order" is different from the RCS "merge" program merge object order. In the above ordering, the original is first. But the argument order to the 3-way merge program "merge" is to have the original in the middle. Don't ask me why. Examples: torvalds@ppc970:~/merge-test> merge-cache cat MM This is MM from the original tree. # original This is modified MM in the branch A. # merge1 This is modified MM in the branch B. # merge2 This is modified MM in the branch B. # current contents or torvalds@ppc970:~/merge-test> merge-cache cat AA MM cat: : No such file or directory This is added AA in the branch A. This is added AA in the branch B. This is added AA in the branch B. fatal: merge program failed where the latter example shows how "merge-cache" will stop trying to merge once anything has returned an error (ie "cat" returned an error for the AA file, because it didn't exist in the original, and thus "merge-cache" didn't even try to merge the MM thing). ################################################################ read-tree read-tree ( | -m [ ])" Reads the tree information given by into the directory cache, but does not actually _update_ any of the files it "caches". (see: checkout-cache) Optionally, it can merge a tree into the cache or perform a 3-way merge. Trivial merges are done by read-tree itself. Only conflicting paths will be in unmerged state when read-tree returns. -m Perform a merge, not just a read The id of the tree object(s) to be read/merged. Merging If -m is specified, read-tree performs 2 kinds of merge, a single tree merge if only 1 tree is given or a 3-way merge if 3 trees are provided. Single Tree Merge If only 1 tree is specified, read-tree operates as if the user did not specify "-m", except that if the original cache has an entry for a given pathname; and the contents of the path matches with the tree being read, the stat info from the cache is used. (In other words, the cache's stat()s take precedence over the merged tree's) That means that if you do a "read-tree -m " followed by a "checkout-cache -f -a", the checkout-cache only checks out the stuff that really changed. This is used to avoid unnecessary false hits when show-diff is run after read-tree. 3-Way Merge Each "index" entry has two bits worth of "stage" state. stage 0 is the normal one, and is the only one you'd see in any kind of normal use. However, when you do "read-tree" with multiple trees, the "stage" starts out at 0, but increments for each tree you read. And in particular, the "-m" flag means "start at stage 1" instead. This means that you can do read-tree -m and you will end up with an index with all of the entries in "stage1", all of the entries in "stage2" and all of the entries in "stage3". Furthermore, "read-tree" has special-case logic that says: if you see a file that matches in all respects in the following states, it "collapses" back to "stage0": - stage 2 and 3 are the same; take one or the other (it makes no difference - the same work has been done on stage 2 and 3) - stage 1 and stage 2 are the same and stage 3 is different; take stage 3 (some work has been done on stage 3) - stage 1 and stage 3 are the same and stage 2 is different take stage 2 (some work has been done on stage 2) Write-tree refuses to write a nonsensical tree, so write-tree will complain about unmerged entries if it sees a single entry that is not stage 0". Ok, this all sounds like a collection of totally nonsensical rules, but it's actually exactly what you want in order to do a fast merge. The different stages represent the "result tree" (stage 0, aka "merged"), the original tree (stage 1, aka "orig"), and the two trees you are trying to merge (stage 2 and 3 respectively). In fact, the way "read-tree" works, it's entirely agnostic about how you assign the stages, and you could really assign them any which way, and the above is just a suggested way to do it (except since "write-tree" refuses to write anything but stage0 entries, it makes sense to always consider stage 0 to be the "full merge" state). So what happens? Try it out. Select the original tree, and two trees to merge, and look how it works: - if a file exists in identical format in all three trees, it will automatically collapse to "merged" state by the new read-tree. - a file that has _any_ difference what-so-ever in the three trees will stay as separate entries in the index. It's up to "script policy" to determine how to remove the non-0 stages, and insert a merged version. But since the index is always sorted, they're easy to find: they'll be clustered together. - the index file saves and restores with all this information, so you can merge things incrementally, but as long as it has entries in stages 1/2/3 (ie "unmerged entries") you can't write the result. So now the merge algorithm ends up being really simple: - you walk the index in order, and ignore all entries of stage 0, since they've already been done. - if you find a "stage1", but no matching "stage2" or "stage3", you know it's been removed from both trees (it only existed in the original tree), and you remove that entry. - if you find a matching "stage2" and "stage3" tree, you remove one of them, and turn the other into a "stage0" entry. Remove any matching "stage1" entry if it exists too. .. all the normal trivial rules .. Incidentally - it also means that you don't even have to have a separate subdirectory for this. All the information literally is in the index file, which is a temporary thing anyway. There is no need to worry about what is in the working directory, since it is never shown and never used. see also: write-tree show-files ################################################################ rev-list Lists commit objects in reverse chronological order starting at the given commit, taking ancestry relationship into account. This is useful to produce human-readable log output. ################################################################ rev-tree rev-tree [--edges] [--cache ] [^] [[^]] Provides the revision tree for one or more commits. --edges Show edges (ie places where the marking changes between parent and child) --cache Use the specified file as a cache. [Not implemented yet] [^] The commit id to trace (a leading caret means to ignore this commit-id and below) Output: : [: ]* Date in 'seconds since epoch' id of commit object id of each parent commit object (>1 indicates a merge) The flags are read as a bitmask representing each commit provided on the commandline. eg: given the command: $ rev-tree The output: :5 means that is reachable from (1) and (4) A revtree can get quite large. rev-tree will eventually allow you to cache previous state so that you don't have to follow the whole thing down. So the change difference between two commits is literally rev-tree [commit-id1] > commit1-revtree rev-tree [commit-id2] > commit2-revtree join -t : commit1-revtree commit2-revtree > common-revisions (this is also how to find the most common parent - you'd look at just the head revisions - the ones that aren't referred to by other revisions - in "common-revision", and figure out the best one. I think.) ################################################################ show-diff show-diff [-p] [-q] [-s] [-z] [paths...] Compares the files in the working tree and the cache. When paths are specified, compares only those named paths. Otherwise all entries in the cache are compared. The output format is the same as diff-cache and diff-tree. -p generate patch (see section on generating patches) -q Remain silent even on nonexisting files -s Does not do anything other than what -q does. Output format: See "Output format from diff-cache, diff-tree and show-diff" section. ################################################################ show-files show-files [-z] [-t] (--[cached|deleted|others|ignored|stage|unmerged])* (-[c|d|o|i|s|u])* [-x |--exclude=] [-X |--exclude-from=] This merges the file listing in the directory cache index with the actual working directory list, and shows different combinations of the two. One or more of the options below may be used to determine the files shown: -c|--cached Show cached files in the output (default) -d|--deleted Show deleted files in the output -o|--others Show other files in the output -i|--ignored Show ignored files in the output Note the this also reverses any exclude list present. -s|--stage Show stage files in the output -u|--unmerged Show unmerged files in the output (forces --stage) #-t [not in Linus' tree (yet?)] # Identify the file status with the following tags (followed by # a space) at the start of each line: # H cached # M unmerged # R removed/deleted # ? other -z \0 line termination on output -x|--exclude= Skips files matching pattern. Note that pattern is a shell wildcard pattern. -X|--exclude-from= exclude patterns are read from ; 1 per line. Allows the use of the famous dontdiff file as follows to find out about uncommitted files just as dontdiff is used with the diff command: show-files --others --exclude-from=dontdiff Output show files just outputs the filename unless --stage is specified in which case it outputs: [ ] show-files --unmerged" and "show-files --stage " can be used to examine detailed information on unmerged paths. For an unmerged path, instead of recording a single mode/SHA1 pair, the dircache records up to three such pairs; one from tree O in stage 1, A in stage 2, and B in stage 3. This information can be used by the user (or Cogito) to see what should eventually be recorded at the path. (see read-cache for more information on state) see also: read-cache ################################################################ unpack-file unpack-file Creates a file holding the contents of the blob specified by sha1. It returns the name of the temporary file in the following format: .merge_file_XXXXX Must be a blob id ################################################################ update-cache update-cache [--add] [--remove] [--refresh [--ignore-missing]] [--cacheinfo ]* [--] []* Modifies the index or directory cache. Each file mentioned is updated into the cache and any 'unmerged' or 'needs updating' state is cleared. The way update-cache handles files it is told about can be modified using the various options: --add If a specified file isn't in the cache already then it's added. Default behaviour is to ignore new files. --remove If a specified file is in the cache but is missing then it's removed. Default behaviour is to ignore removed file. --refresh Looks at the current cache and checks to see if merges or updates are needed by checking stat() information. --ignore-missing Ignores missing files during a --refresh --cacheinfo Directly insert the specified info into the cache. -- Do not interpret any more arguments as options. Files to act on. Note that files begining with '.' are discarded. This includes "./file" and "dir/./file". If you don't want this, then use cleaner names. The same applies to directories ending '/' and paths with '//' Using --refresh --refresh does not calculate a new sha1 file or bring the cache up-to-date for mode/content changes. But what it _does_ do is to "re-match" the stat information of a file with the cache, so that you can refresh the cache for a file that hasn't been changed but where the stat entry is out of date. For example, you'd want to do this after doing a "read-tree", to link up the stat cache details with the proper files. Using --cacheinfo --cacheinfo is used to register a file that is not in the current working directory. This is useful for minimum-checkout merging. To pretend you have a file with mode and sha1 at path, say: $ update-cache --cacheinfo mode sha1 path To update and refresh only the files already checked out: checkout-cache -n -f -a && update-cache --ignore-missing --refresh ################################################################ write-tree write-tree Creates a tree object using the current cache. The cache must be merged. Conceptually, write-tree sync()s the current directory cache contents into a set of tree files. In order to have that match what is actually in your directory right now, you need to have done a "update-cache" phase before you did the "write-tree". ################################################################ Output format from diff-cache, diff-tree and show-diff. These commands all compare two sets of things; what are compared are different: diff-cache compares the and the files on the filesystem. diff-cache --cached compares the and the cache. diff-tree [-r] [paths...] compares the trees named by the two arguments. show-diff [paths...] compares the cache and the files on the filesystem. The following desription uses "old" and "new" to mean those compared entities. For files in old but not in new (i.e. removed): - \t \t \t For files not in old but in new (i.e. added): + \t \t \t For files that differ: *-> \t \t -> \t is shown as all 0's if new is a file on the filesystem and it is out of sync with the cache. Example: *100644->100660 blob 5be4a414b32cf4204f889469942986d3d783da84->0000000000000000000000000000000000000000 file.c ################################################################ Generating patches When diff-cache, diff-tree, or show-diff are run with a -p option, they do not produce the output described in "Output format from diff-cache, diff-tree and show-diff" section. It instead produces a patch file. The patch generation can be customized at two levels. This customization also applies to diff-tree-helper. 1. When the environment variable GIT_EXTERNAL_DIFF is not set, these commands internally invoke diff like this: diff -L k/ -L l/ -pu For added files, /dev/null is used for . For removed files, /dev/null is used for The first part of the above command-line can be customized via the environment variable GIT_DIFF_CMD. For example, if you do not want to show the extra level of leading path, you can say this: GIT_DIFF_CMD="diff -L'%s' -L'%s'" show-diff -p Caution: Do not use more than two '%s' in GIT_DIFF_CMD. The diff formatting options can be customized via the environment variable GIT_DIFF_OPTS. For example, if you prefer context diff: GIT_DIFF_OPTS=-c diff-cache -p $(cat .git/HEAD) 2. When the environment variable GIT_EXTERNAL_DIFF is set, the program named by it is called, instead of the diff invocation described above. For a path that is added, removed, or modified, GIT_EXTERNAL_DIFF is called with 7 parameters: path old-file old-hex old-mode new-file new-hex new-mode where -file are files GIT_EXTERNAL_DIFF can use to read the contents of , -hex are the 40-hexdigit SHA1 hashes, -mode are the octal representation of the file modes. The file parameters can point at the user's working file (e.g. new-file in show-diff), /dev/null (e.g. old-file when a new file is added), or a temporary file (e.g. old-file in the cache). GIT_EXTERNAL_DIFF should not worry about unlinking the temporary file --- it is removed when GIT_EXTERNAL_DIFF exits. For a path that is unmerged, GIT_EXTERNAL_DIFF is called with 1 parameter, path. ################################################################ Terminology: - see README for description Each line contains terms used interchangeably object database, .git directory directory cache, index id, sha1, sha1-id, sha1 hash type, tag blob, blob object tree, tree object commit, commit object parent root object changeset git Environment Variables AUTHOR_NAME AUTHOR_EMAIL AUTHOR_DATE COMMIT_AUTHOR_NAME COMMIT_AUTHOR_EMAIL GIT_DIFF_CMD GIT_DIFF_OPTS GIT_EXTERNAL_DIFF GIT_INDEX_FILE SHA1_FILE_DIRECTORY