1The output format from "git-diff-cache", "git-diff-tree" and 2"git-diff-files" is very similar. 3 4These commands all compare two sets of things; what are 5compared are different: 6 7git-diff-cache <tree-ish>:: 8 compares the <tree-ish> and the files on the filesystem. 9 10git-diff-cache --cached <tree-ish>:: 11 compares the <tree-ish> and the cache. 12 13git-diff-tree [-r] <tree-ish-1> <tree-ish-2> [<pattern>...]:: 14 compares the trees named by the two arguments. 15 16git-diff-files [<pattern>...]:: 17 compares the cache and the files on the filesystem. 18 19 20An output line is formatted this way: 21 22in-place edit :100644 100644 bcd1234... 0123456... M file0 23copy-edit :100644 100644 abcd123... 1234567... C68 file1 file2 24rename-edit :100644 100644 abcd123... 1234567... R86 file1 file3 25create :000000 100644 0000000... 1234567... N file4 26delete :100644 000000 1234567... 0000000... D file5 27unmerged :000000 000000 0000000... 0000000... U file6 28 29That is, from the left to the right: 30 31 (1) a colon. 32 (2) mode for "src"; 000000 if creation or unmerged. 33 (3) a space. 34 (4) mode for "dst"; 000000 if deletion or unmerged. 35 (5) a space. 36 (6) sha1 for "src"; 0{40} if creation or unmerged. 37 (7) a space. 38 (8) sha1 for "dst"; 0{40} if creation, unmerged or "look at work tree". 39 (9) status, followed by optional "score" number. 40 (10) a tab or a NUL when '-z' option is used. 41 (11) path for "src" 42 (12) a tab or a NUL when '-z' option is used; only exists for C or R. 43 (13) path for "dst"; only exists for C or R. 44 (14) an LF or a NUL when '-z' option is used, to terminate the record. 45 46<sha1> is shown as all 0's if new is a file on the filesystem 47and it is out of sync with the cache. Example: 48 49 :100644 100644 5be4a4...... 000000...... M file.c 50 51Generating patches with -p 52-------------------------- 53 54When "git-diff-cache", "git-diff-tree", or "git-diff-files" are run 55with a '-p' option, they do not produce the output described above 56instead they produce a patch file. 57 58The patch generation can be customized at two levels. This 59customization also applies to "git-diff-helper". 60 611. When the environment variable 'GIT_EXTERNAL_DIFF' is not set, 62 these commands internally invoke "diff" like this: 63 64 diff -L a/<path> -L a/<path> -pu <old> <new> 65+ 66For added files, `/dev/null` is used for <old>. For removed 67files, `/dev/null` is used for <new> 68+ 69The "diff" formatting options can be customized via the 70environment variable 'GIT_DIFF_OPTS'. For example, if you 71prefer context diff: 72 73 GIT_DIFF_OPTS=-c git-diff-cache -p $(cat .git/HEAD) 74 75 762. When the environment variable 'GIT_EXTERNAL_DIFF' is set, the 77 program named by it is called, instead of the diff invocation 78 described above. 79+ 80For a path that is added, removed, or modified, 81'GIT_EXTERNAL_DIFF' is called with 7 parameters: 82 83 path old-file old-hex old-mode new-file new-hex new-mode 84+ 85where: 86 87 <old|new>-file:: are files GIT_EXTERNAL_DIFF can use to read the 88 contents of <old|ne>, 89 <old|new>-hex:: are the 40-hexdigit SHA1 hashes, 90 <old|new>-mode:: are the octal representation of the file modes. 91 92+ 93The file parameters can point at the user's working file 94(e.g. `new-file` in "git-diff-files"), `/dev/null` (e.g. `old-file` 95when a new file is added), or a temporary file (e.g. `old-file` in the 96cache). 'GIT_EXTERNAL_DIFF' should not worry about unlinking the 97temporary file --- it is removed when 'GIT_EXTERNAL_DIFF' exits. 98 99For a path that is unmerged, 'GIT_EXTERNAL_DIFF' is called with 1 100parameter, <path>.