1git-rev-parse(1) 2================ 3 4NAME 5---- 6git-rev-parse - Pick out and massage parameters 7 8 9SYNOPSIS 10-------- 11'git-rev-parse' [ --option ] <args>... 12 13DESCRIPTION 14----------- 15 16Many git porcelainish commands take mixture of flags 17(i.e. parameters that begin with a dash '-') and parameters 18meant for underlying `git-rev-list` command they use internally 19and flags and parameters for other commands they use as the 20downstream of `git-rev-list`. This command is used to 21distinguish between them. 22 23 24OPTIONS 25------- 26--revs-only:: 27 Do not output flags and parameters not meant for 28 `git-rev-list` command. 29 30--no-revs:: 31 Do not output flags and parameters meant for 32 `git-rev-list` command. 33 34--flags:: 35 Do not output non-flag parameters. 36 37--no-flags:: 38 Do not output flag parameters. 39 40--default <arg>:: 41 If there is no parameter given by the user, use `<arg>` 42 instead. 43 44--verify:: 45 The parameter given must be usable as a single, valid 46 object name. Otherwise barf and abort. 47 48--sq:: 49 Usually the output is made one line per flag and 50 parameter. This option makes output a single line, 51 properly quoted for consumption by shell. Useful when 52 you expect your parameter to contain whitespaces and 53 newlines (e.g. when using pickaxe `-S` with 54 `git-diff-\*`). 55 56--not:: 57 When showing object names, prefix them with '{caret}' and 58 strip '{caret}' prefix from the object names that already have 59 one. 60 61--symbolic:: 62 Usually the object names are output in SHA1 form (with 63 possible '{caret}' prefix); this option makes them output in a 64 form as close to the original input as possible. 65 66 67--all:: 68 Show all refs found in `$GIT_DIR/refs`. 69 70--branches:: 71 Show branch refs found in `$GIT_DIR/refs/heads`. 72 73--tags:: 74 Show tag refs found in `$GIT_DIR/refs/tags`. 75 76--remotes:: 77 Show tag refs found in `$GIT_DIR/refs/remotes`. 78 79--show-prefix:: 80 When the command is invoked from a subdirectory, show the 81 path of the current directory relative to the top-level 82 directory. 83 84--show-cdup:: 85 When the command is invoked from a subdirectory, show the 86 path of the top-level directory relative to the current 87 directory (typically a sequence of "../", or an empty string). 88 89--git-dir:: 90 Show `$GIT_DIR` if defined else show the path to the .git directory. 91 92--short, --short=number:: 93 Instead of outputting the full SHA1 values of object names try to 94 abbreviate them to a shorter unique name. When no length is specified 95 7 is used. The minimum length is 4. 96 97--since=datestring, --after=datestring:: 98 Parses the date string, and outputs corresponding 99 --max-age= parameter for git-rev-list command. 100 101--until=datestring, --before=datestring:: 102 Parses the date string, and outputs corresponding 103 --min-age= parameter for git-rev-list command. 104 105<args>...:: 106 Flags and parameters to be parsed. 107 108 109SPECIFYING REVISIONS 110-------------------- 111 112A revision parameter typically, but not necessarily, names a 113commit object. They use what is called an 'extended SHA1' 114syntax. Here are various ways to spell object names. The 115ones listed near the end of this list are to name trees and 116blobs contained in a commit. 117 118* The full SHA1 object name (40-byte hexadecimal string), or 119 a substring of such that is unique within the repository. 120 E.g. dae86e1950b1277e545cee180551750029cfe735 and dae86e both 121 name the same commit object if there are no other object in 122 your repository whose object name starts with dae86e. 123 124* An output from `git-describe`; i.e. a closest tag, followed by a 125 dash, a 'g', and an abbreviated object name. 126 127* A symbolic ref name. E.g. 'master' typically means the commit 128 object referenced by $GIT_DIR/refs/heads/master. If you 129 happen to have both heads/master and tags/master, you can 130 explicitly say 'heads/master' to tell git which one you mean. 131 132* A suffix '@' followed by a date specification enclosed in a brace 133 pair (e.g. '\{yesterday\}', '\{1 month 2 weeks 3 days 1 hour 1 134 second ago\}' or '\{1979-02-26 18:30:00\}') to specify the value 135 of the ref at a prior point in time. This suffix may only be 136 used immediately following a ref name and the ref must have an 137 existing log ($GIT_DIR/logs/<ref>). 138 139* A suffix '{caret}' to a revision parameter means the first parent of 140 that commit object. '{caret}<n>' means the <n>th parent (i.e. 141 'rev{caret}' 142 is equivalent to 'rev{caret}1'). As a special rule, 143 'rev{caret}0' means the commit itself and is used when 'rev' is the 144 object name of a tag object that refers to a commit object. 145 146* A suffix '{tilde}<n>' to a revision parameter means the commit 147 object that is the <n>th generation grand-parent of the named 148 commit object, following only the first parent. I.e. rev~3 is 149 equivalent to rev{caret}{caret}{caret} which is equivalent to\ 150 rev{caret}1{caret}1{caret}1. 151 152* A suffix '{caret}' followed by an object type name enclosed in 153 brace pair (e.g. `v0.99.8{caret}\{commit\}`) means the object 154 could be a tag, and dereference the tag recursively until an 155 object of that type is found or the object cannot be 156 dereferenced anymore (in which case, barf). `rev{caret}0` 157 introduced earlier is a short-hand for `rev{caret}\{commit\}`. 158 159* A suffix '{caret}' followed by an empty brace pair 160 (e.g. `v0.99.8{caret}\{\}`) means the object could be a tag, 161 and dereference the tag recursively until a non-tag object is 162 found. 163 164* A suffix ':' followed by a path; this names the blob or tree 165 at the given path in the tree-ish object named by the part 166 before the colon. 167 168* A colon, optionally followed by a stage number (0 to 3) and a 169 colon, followed by a path; this names a blob object in the 170 index at the given path. Missing stage number (and the colon 171 that follows it) names an stage 0 entry. 172 173Here is an illustration, by Jon Loeliger. Both node B and C are 174a commit parents of commit node A. Parent commits are ordered 175left-to-right. 176 177 G H I J 178 \ / \ / 179 D E F 180 \ | / \ 181 \ | / | 182 \|/ | 183 B C 184 \ / 185 \ / 186 A 187 188 A = = A^0 189 B = A^ = A^1 = A~1 190 C = A^2 = A^2 191 D = A^^ = A^1^1 = A~2 192 E = B^2 = A^^2 193 F = B^3 = A^^3 194 G = A^^^ = A^1^1^1 = A~3 195 H = D^2 = B^^2 = A^^^2 = A~2^2 196 I = F^ = B^3^ = A^^3^ 197 J = F^2 = B^3^2 = A^^3^2 198 199 200SPECIFYING RANGES 201----------------- 202 203History traversing commands such as `git-log` operate on a set 204of commits, not just a single commit. To these commands, 205specifying a single revision with the notation described in the 206previous section means the set of commits reachable from that 207commit, following the commit ancestry chain. 208 209To exclude commits reachable from a commit, a prefix `{caret}` 210notation is used. E.g. "`{caret}r1 r2`" means commits reachable 211from `r2` but exclude the ones reachable from `r1`. 212 213This set operation appears so often that there is a shorthand 214for it. "`r1..r2`" is equivalent to "`{caret}r1 r2`". It is 215the difference of two sets (subtract the set of commits 216reachable from `r1` from the set of commits reachable from 217`r2`). 218 219A similar notation "`r1\...r2`" is called symmetric difference 220of `r1` and `r2` and is defined as 221"`r1 r2 --not $(git-merge-base --all r1 r2)`". 222It it the set of commits that are reachable from either one of 223`r1` or `r2` but not from both. 224 225Here are a few examples: 226 227 D A B D 228 D F A B C D F 229 ^A G B D 230 ^A F B C F 231 G...I C D F G I 232 ^B G I C D F G I 233 234Author 235------ 236Written by Linus Torvalds <torvalds@osdl.org> and 237Junio C Hamano <junkio@cox.net> 238 239Documentation 240-------------- 241Documentation by Junio C Hamano and the git-list <git@vger.kernel.org>. 242 243GIT 244--- 245Part of the gitlink:git[7] suite 246