The `darcs initialize` command creates an empty repository in the current directory. This repository lives in a new `_darcs` directory, which stores version control metadata and settings.

Existing files and subdirectories are not touched. You can record them with `darcs record --look-for-adds`.

Initialize is commonly abbreviated to `init`.

Darcs currently supports three kinds of patch semantics. These are called `darcs-1`, `darcs-2`, and `darcs-3`. They are mutually incompatible, that is, you cannot exchange patches between repos with different semantics.

By default, patches of the new repository are in the darcs-2 semantics. However it is possible to create a repository in darcs-1 semantics with the flag `--darcs-1`, althought this is not recommended except for sharing patches with a project that uses patches in the darcs-1 semantics.

The `darcs-3` semantics is EXPERIMENTAL and new in version 2.16. It is included only as a technology preview and we do NOT recommend to use it for any serious work. The on-disk format is not yet finalized and we cannot and will not promise that later releases will work with darcs-3 repos created with any darcs version before 3.0.

Initialize and clone commands create the preferences files in _darcs/prefs/ directory of the newly created repository. With option --with-prefs-templates `boring` and `binaries` preferences files will be filled with default templates. If you want to leave these files empty use --no-prefs-templates option. If you prefer to keep the relevant settings globally, it will be convenient to add 'ALL no-prefs-templates' to your ~/darcs/defaults file.

Generally the working tree contains both files that should be version controlled (such as source code) and files that Darcs should ignore (such as executables compiled from the source code). The `darcs add` command is used to tell Darcs which files to version control.

When an existing project is first imported into a Darcs repository, it is common to run `darcs add -r *` or `darcs record -l` to add all initial source files into darcs.

Adding symbolic links (symlinks) is not supported.

Darcs will ignore all files and folders that look "boring". The `--boring` option overrides this behaviour.

Darcs will not add a file if another file in the same folder has the same name, except for case. The `--case-ok` option overrides this behaviour. Windows and OS X usually use filesystems that do not allow files a folder to have the same name except for case (for example, `ReadMe` and `README`). If `--case-ok` is used, the repository might be unusable on those systems!

The `darcs whatsnew` command lists unrecorded changes to the working tree. If you specify a set of files and directories, only unrecorded changes to those files and directories are listed.

With the `--summary` option, the changes are condensed to one line per file, with mnemonics to indicate the nature and extent of the change. The `--look-for-adds` option causes candidates for `darcs add` to be included in the summary output. WithSummary mnemonics are as follows:

* `A f` and `A d/` respectively mean an added file or directory.
* `R f` and `R d/` respectively mean a removed file or directory.
* `M f -N +M rP` means a modified file, with `N` lines deleted, `M`
lines added, and `P` lexical replacements.
* `f -> g` means a moved file or directory.
* `a f` and `a d/` respectively mean a new, but unadded, file or
directory, when using `--look-for-adds`.
* An exclamation mark (!) as in `R! foo.c`, means the change
conflicts with a change in an earlier patch. The phrase `duplicated`
means the change is identical to a change in an earlier patch.

The `--machine-readable` option implies `--summary` while making it more parsable. Modified files are only shown as `M f`, and moves are shown in two lines: `F f` and `T g` (as in 'From f To g').

By default, `darcs whatsnew` uses Darcs' internal format for changes. To see some context (unchanged lines) around each change, use the `--unified` option. (This option has no effect in interactive mode.) To view changes in conventional `diff` format, use the `darcs diff` command; but note that `darcs diff` cannot properly display changes when file renames are involved.

This command exits unsuccessfully (returns a non-zero exit status) if there are no unrecorded changes.

The `darcs record` command is used to create a patch from changes in the working tree. If you specify a set of files and directories, changes to other files will be skipped.

Every patch has a name, an optional description, an author and a date.

Darcs will launch a text editor (see `darcs help environment`) after the interactive selection, to let you enter the patch name (first line) and the patch description (subsequent lines).

You can supply the patch name in advance with the `-m` option, in which case no text editor is launched, unless you use `--edit-long-comment`.

The patch description is an optional block of free-form text. It is used to supply additional information that doesn't fit in the patch name. For example, it might include a rationale of WHY the change was necessary.

A technical difference between patch name and patch description, is that matching with the flag `-p` is only done on patch names.

Finally, the `--logfile` option allows you to supply a file that already contains the patch name and description. This is useful if a previous record failed and left a `_darcs/patch_description.txt` file.

Each patch is attributed to its author, usually by email address (for example, `Fred Bloggs <fred@example.net>`). Darcs looks in several places for this author string: the `--author` option, the files `_darcs/prefs/author` (in the repository) and `~/.darcs/author` (in your home directory), and the environment variables `$DARCS_EMAIL` and `$EMAIL`. If none of those exist, Darcs will prompt you for an author string and write it to `~/.darcs/author`. Note that if you have more than one email address, you can put them all in `~/.darcs/author`, one author per line. Darcs will still prompt you for an author, but it allows you to select from the list, or to type in an alternative.

If you want to manually define any explicit dependencies for your patch, you can use the `--ask-deps` flag. Some dependencies may be automatically inferred from the patch's content and cannot be removed. A patch with specific dependencies can be empty.

The patch date is generated automatically. It can only be spoofed by using the `--pipe` option.

If you run record with the `--pipe` option, you will be prompted for the patch date, author, and the long comment. The long comment will extend until the end of file or stdin is reached. This interface is intended for scripting darcs, in particular for writing repository conversion scripts. The prompts are intended mostly as a useful guide (since scripts won't need them), to help you understand the input format. Here's an example of what the `--pipe` prompts look like:

What is the date? Mon Nov 15 13:38:01 EST 2004
Who is the author? David Roundy
What is the log? One or more comment lines

If a test command has been defined with `darcs setpref`, attempting to record a patch will cause the test command to be run in a clean copy of the working tree (that is, including only recorded changes). If the test fails, you will be offered to abort the record operation.

The `--set-scripts-executable` option causes scripts to be made executable in the clean copy of the working tree, prior to running the test. See `darcs clone` for an explanation of the script heuristic.

If your test command is tediously slow (e.g. `make all`) and you are recording several patches in a row, you may wish to use `--no-test` to skip all but the final test.

To see some context (unchanged lines) around each change, use the `--unified` option.

Clone creates a copy of a repository. The optional second argument specifies a destination directory for the new copy; if omitted, it is inferred from the source location.

By default Darcs will copy every patch from the original repository. If you expect the original repository to remain accessible, you can use `--lazy` to avoid copying patches until they are needed ('copy on demand'). This is particularly useful when copying a remote repository with a long history that you don't care about.

When cloning locally, Darcs automatically uses hard linking where possible. As well as saving time and space, this enables to move or delete the original repository without affecting the copy. Hard linking requires that the copy be on the same filesystem as the original repository, and that the filesystem support hard linking. This includes NTFS, HFS+ and all general-purpose Unix filesystems (such as ext, UFS and ZFS). FAT does not support hard links.

When cloning from a remote location, Darcs will look for and attempt to use packs created by `darcs optimize http` in the remote repository. Packs are single big files that can be downloaded faster than many little files.

Darcs clone will not copy unrecorded changes to the source repository's working tree.

You can copy a repository to a ssh url, in which case the new repository will always be complete.

It is often desirable to make a copy of a repository that excludes some patches. For example, if releases are tagged then `darcs clone --tag .` would make a copy of the repository as at the latest release. An untagged repository state can still be identified unambiguously by a context file, as generated by `darcs log --context`. Given the name of such a file, the `--context` option will create a repository that includes only the patches from that context. When a user reports a bug in an unreleased version of your project, the recommended way to find out exactly what version they were running is to have them include a context file in the bug report. You can also make a copy of an untagged state using the `--to-patch` or `--to-match` options, which exclude patches *after* the first matching patch. Because these options treat the set of patches as an ordered sequence, you may get different results after reordering with `darcs optimize reorder`.

The `--set-scripts-executable` option causes scripts to be made executable in the working tree. A script is any file that starts with a shebang ("#!").

The --inherit-default option is meant to support a work flow where you have different branches of the same upstream repository and want all your branches to have the same upstream repo as the defaultrepo. It is most useful when enabled globally by adding 'ALL --inherit-default' to your ~/darcs/defaults file.

For the clone command it means the following: If the source repository already has a defaultrepo set (either because you cloned it or because you explicitly used the --set-default option), and both source and target are locally valid paths on the same host, then the target repo will get the same defaultrepo as the source repo. Otherwise the target repo gets the source repo itself as defaultrepo, i.e. we fall back to the defalt behavior (--no-inherit-default).

Initialize and clone commands create the preferences files in _darcs/prefs/ directory of the newly created repository. With option --with-prefs-templates `boring` and `binaries` preferences files will be filled with default templates. If you want to leave these files empty use --no-prefs-templates option. If you prefer to keep the relevant settings globally, it will be convenient to add 'ALL no-prefs-templates' to your ~/darcs/defaults file.

Pull is used to bring patches made in another repository into the current repository (that is, either the one in the current directory, or the one specified with the `--repodir` option). Pull accepts arguments, which are URLs from which to pull, and when called without an argument, pull will use the repository specified at `_darcs/prefs/defaultrepo`.

The default (`--union`) behavior is to pull any patches that are in any of the specified repositories. If you specify the `--intersection` flag, darcs will only pull those patches which are present in all source repositories. If you specify the `--complement` flag, darcs will only pull elements in the first repository that do not exist in any of the remaining repositories.

If `--reorder` is supplied, the set of patches that exist only in the current repository is brought at the top of the current history. This will work even if there are no new patches to pull.

The --inherit-default option is meant to support a work flow where you have different branches of the same upstream repository and want all your branches to have the same upstream repo as the defaultrepo. It is most useful when enabled globally by adding 'ALL --inherit-default' to your ~/darcs/defaults file.

For the commands push, pull, and send it means the following: Changes the meaning of the --set-default option so that it sets the (local) defaultrepo to the defaultrepo of the remote repo, instead of the remote repo itself. This happens only if the remote repo does have a defaultrepo set and both local and remote repositories are locally valid paths on the same host, otherwise fall back to the default behavior (--no-inherit-default).

See `darcs help apply` for detailed description of many options.

Push is the opposite of pull. Push allows you to copy patches from the current repository into another repository.

The --reorder-patches option works in the same way as it does for pull and apply: instead of placing the new patches (coming from your local repository) on top of (i.e. after) the existing (remote) ones, it puts the remote-only patches on top of the ones that you are pushing. This can be useful, for instance, if you have recorded a tag locally and want this tag to be clean in the remote repository after pushing.

If you give the `--apply-as` flag, darcs will use `sudo` to apply the patches as a different user. This can be useful if you want to set up a system where several users can modify the same repository, but you don't want to allow them full write access. This isn't secure against skilled malicious attackers, but at least can protect your repository from clumsy, inept or lazy users.

`darcs push` will compress the patch data before sending it to a remote location via ssh. This works as long as the remote darcs is not older than version 2.5. If you get errors that indicate a corrupt patch bundle, you should try again with the `--no-compress` option.

The --inherit-default option is meant to support a work flow where you have different branches of the same upstream repository and want all your branches to have the same upstream repo as the defaultrepo. It is most useful when enabled globally by adding 'ALL --inherit-default' to your ~/darcs/defaults file.

For the commands push, pull, and send it means the following: Changes the meaning of the --set-default option so that it sets the (local) defaultrepo to the defaultrepo of the remote repo, instead of the remote repo itself. This happens only if the remote repo does have a defaultrepo set and both local and remote repositories are locally valid paths on the same host, otherwise fall back to the default behavior (--no-inherit-default).

Darcs cannot reliably distinguish between a file being deleted and a new one added, and a file being moved. Therefore Darcs always assumes the former, and provides the `darcs mv` command to let Darcs know when you want the latter. This command will also move the file in the working tree (unlike `darcs remove`), unless it has already been moved.

Darcs will not rename a file if another file in the same folder has the same name, except for case. The `--case-ok` option overrides this behaviour. Windows and OS X usually use filesystems that do not allow files a folder to have the same name except for case (for example, `ReadMe` and `README`). If `--case-ok` is used, the repository might be unusable on those systems!

The `darcs remove` command exists primarily for symmetry with `darcs add`, as the normal way to remove a file from version control is simply to delete it from the working tree. This command is only useful in the unusual case where one wants to record a removal patch WITHOUT deleting the copy in the working tree (which can be re-added).

Note that applying a removal patch to a repository (e.g. by pulling the patch) will ALWAYS affect the working tree of that repository.

In addition to line-based patches, Darcs supports a limited form of lexical substitution. Files are treated as sequences of words, and each occurrence of the old word is replaced by the new word. This is intended to provide a clean way to rename a function or variable. Such renamings typically affect lines all through the source code, so a traditional line-based patch would be very likely to conflict with other branches, requiring manual merging.

Files are tokenized according to one simple rule: words are strings of valid token characters, and everything between them (punctuation and whitespace) is discarded. By default, valid token characters are letters, numbers and the underscore (i.e. `[A-Za-z0-9_]`). However if the old and/or new token contains either a hyphen or period, BOTH hyphen and period are treated as valid (i.e. `[A-Za-z0-9_.-]`).

The set of valid characters can be customized using the `--token-chars` option. The argument must be surrounded by square brackets. If a hyphen occurs between two characters in the set, it is treated as a set range. For example, in most locales `[A-Z]` denotes all uppercase letters. If the first character is a caret, valid tokens are taken to be the complement of the remaining characters. For example, `[^:0` could be used to match fields in the passwd(5), where records and fields are separated by newlines and colons respectively.

If you choose to use `--token-chars`, you are STRONGLY encouraged to do so consistently. The consequences of using multiple replace patches with different `--token-chars` arguments on the same file are not well tested nor well understood.

By default Darcs will refuse to perform a replacement if the new token is already in use, because the replacements would be not be distinguishable from the existing tokens. This behaviour can be overridden by supplying the `--force` option, but an attempt to `darcs rollback` the resulting patch will affect these existing tokens.

Limitations:

The tokenizer treats files as byte strings, so it is not possible for `--token-chars` to include multi-byte characters, such as the non-ASCII parts of UTF-8. Similarly, trying to replace a "high-bit" character from a unibyte encoding will also result in replacement of the same byte in files with different encodings. For example, an acute a from ISO 8859-1 will also match an alpha from ISO 8859-7.

Due to limitations in the patch file format, `--token-chars` arguments cannot contain literal whitespace. For example, `[^ 0t]` cannot be used to declare all characters except the space, tab and newline as valid within a word, because it contains a literal space.

Unlike POSIX regex(7) bracket expressions, character classes (such as `[[:alnum:]]`) are NOT supported by `--token-chars`, and will be silently treated as a simple set of characters.

The `darcs log` command lists patches of the current repository or, with `--repo`, a remote repository. Without options or arguments, ALL patches will be listed.

When given files or directories paths as arguments, only patches which affect those paths are listed. This includes patches that happened to files before they were moved or renamed.

When given `--from-tag` or `--from-patch`, only patches since that tag or patch are listed. Similarly, the `--to-tag` and `--to-patch` options restrict the list to older patches.

The `--last` and `--max-count` options both limit the number of patches listed. The former applies BEFORE other filters, whereas the latter applies AFTER other filters. For example `darcs log foo.c --max-count 3` will print the last three patches that affect foo.c, whereas `darcs log --last 3 foo.c` will, of the last three patches, print only those that affect foo.c.

Four output formats exist. The default is `--human-readable`. The slightly different `--machine-readable` format enables to see patch dependencies in non-interactive mode. You can also select `--context`, which is an internal format that can be re-read by Darcs (e.g. `darcs clone --context`).

Finally, there is `--xml-output`, which emits valid XML... unless a the patch metadata (author, name or description) contains a non-ASCII character and was recorded in a non-UTF8 locale.

When `darcs annotate` is called on a file, it will find the patch that last modified each line in that file. This also works on directories.

The `--machine-readable` option can be used to generate output for machine postprocessing.

The `darcs diff` command compares two versions of the working tree of the current repository. Without options, the pristine (recorded) and unrecorded working trees are compared. This is lower-level than the `darcs whatsnew` command, since it outputs a line-by-line diff, and it is also slower. As with `darcs whatsnew`, if you specify files or directories, changes to other files are not listed. The command always uses an external diff utility.

With the `--patch` option, the comparison will be made between working trees with and without that patch. Patches *after* the selected patch are not present in either of the compared working trees. The `--from-patch` and `--to-patch` options allow the set of patches in the `old' and `new' working trees to be specified separately.

The associated tag and match options are also understood, e.g. `darcs diff --from-tag 1.0 --to-tag 1.1`. All these options assume an ordering of the patch set, so results may be affected by operations such as `darcs optimize reorder`.

diff(1) is always called with the arguments `-rN` and by default also with `-u` to show the differences in unified format. This can be turned off by passing `--no-unified`. An additional argument can be passed using `--diff-opts`, such as `--diff-opts=-ud` or `--diff-opts=-wU9`.

The `--diff-command` option can be used to specify an alternative utility. Arguments may be included, separated by whitespace. The value is not interpreted by a shell, so shell constructs cannot be used. The arguments %1 and %2 MUST be included, these are substituted for the two working trees being compared. For instance:

darcs diff -p . --diff-command "meld %1 %2"

If this option is used, `--diff-opts` is ignored.

Display various information about a repository. See description of the subcommands for details.

Show contents can be used to display an earlier version of some file(s). If you give show contents no version arguments, it displays the recorded version of the file(s).

This command creates a graph of the dependencies between patches. The output format is the Dot Language, see https://www.graphviz.org/doc/info/lang.html. The resulting graph is transitively reduced, in other words, it contains only the direct dependencies, not the indirect ones.

By default all patches in your repository are considered. You can limit this to a range of patches using patch matching options, see `darcs help patterns` and the options avaiable for this command. For instance, to visualize the dependencies between all patches since the last tag, do:

darcs show dependencies --from-tag=. | dot -Tpdf -o FILE.pdf

This command can take a very(!) long time to compute its result, depending on the number of patches in the selected range. For N patches it needs to do on the order of N^3 commutations in the worst case.

The `darcs show files` command lists those files and directories in the working tree that are under version control. This command is primarily for scripting purposes; end users will probably want `darcs whatsnew --summary`.

A file is "pending" if it has been added but not recorded. By default, pending files (and directories) are listed; the `--no-pending` option prevents this.

By default `darcs show files` lists both files and directories, but the `--no-files` and `--no-directories` flags modify this behaviour.

By default entries are one-per-line (i.e. newline separated). This can cause problems if the files themselves contain newlines or other control characters. To get around this, the `--null` option uses the null character instead. The script interpreting output from this command needs to understand this idiom; `xargs -0` is such a command.

For example, to list version-controlled files by size:

darcs show files -0 | xargs -0 ls -ldS

The `darcs show index` command lists all version-controlled files and directories along with their hashes as stored in `_darcs/index`. For files, the fields correspond to file size, sha256 of the current file content and the filename.

The `darcs show pristine` command lists all version-controlled files and directories along with the hashes of their pristine copies. For files, the fields correspond to file size, sha256 of the pristine file content and the filename.

The `darcs show repo` command displays statistics about the current repository, allowing third-party scripts to access this information without inspecting `_darcs` directly (and without breaking when the `_darcs` format changes).

The 'Weak Hash' identifies the set of patches of a repository independently of ordering. It can be used to easily compare two repositories of a same project. It is not cryptographically secure.

By default, output includes statistics that require walking through the patches recorded in the repository, namely the 'Weak Hash' and the count of patches. If this data isn't needed, use `--no-enum-patches` to accelerate this command from O(n) to O(1).

By default, output is in a human-readable format. The `--xml-output` option can be used to generate output for machine postprocessing.

The `darcs show authors` command lists the authors of the current repository, sorted by the number of patches contributed. With the `--verbose` option, this command simply lists the author of each patch (without aggregation or sorting).

An author's name or email address may change over time. To tell Darcs when multiple author strings refer to the same individual, create an `.authorspellings` file in the root of the working tree. Each line in this file begins with an author's canonical name and address, and may be followed by a comma separated list of extended regular expressions. Blank lines and lines beginning with two hyphens are ignored. The format of `.authorspelling` can be described by this pattern:

name <address> [, regexp ]*

There are some pitfalls concerning special characters: Whitespaces are stripped, if you need space in regexp use [ ]. Because comma serves as a separator you have to escape it if you want it in regexp. Note that `.authorspelling` use extended regular expressions so +, ? and so on are metacharacters and you need to escape them to be interpreted literally.

Any patch with an author string that matches the canonical address or any of the associated regexps is considered to be the work of that author. All matching is case-insensitive and partial (it can match a substring). Use ^,$ to match the whole string in regexps

Currently this canonicalization step is done only in `darcs show authors`. Other commands, such as `darcs log` use author strings verbatim.

An example `.authorspelling` file is:

-- This is a comment.
Fred Nurk <fred@example.com>
John Snagge <snagge@bbc.co.uk>, John, snagge@, js@(si|mit).edu
Chuck Jones Jr. <chuck@pobox.com>, cj+user@example.com

The tags command writes a list of all tags in the repository to standard output.

Tab characters (ASCII character 9) in tag names are changed to spaces for better interoperability with shell tools. A warning is printed if this happens.

When given the `--verbose` flag, the command dumps the complete content of the patch index and checks its integrity.

Run test on the current recorded state of the repository. Given no arguments, it uses the default repository test (see `darcs setpref`). Given one argument, it treats it as a test command. Given two arguments, the first is an initialization command and the second is the test (meaning the exit code of the first command is not taken into account to determine success of the test). If given the `--linear` or `--bisect` flags, it tries to find the most recent version in the repository which passes a test.

`--linear` does linear search starting from head, and moving away from head. This strategy is best when the test runs very quickly or the patch you're seeking is near the head.

`--bisect` does binary search. This strategy is best when the test runs very slowly or the patch you're seeking is likely to be in the repository's distant past.

`--backoff` starts searching from head, skipping further and further into the past until the test succeeds. It then does a binary search on a subset of those skipped patches. This strategy works well unless the patch you're seeking is in the repository's distant past.

Under the assumption that failure is monotonous, `--linear` and `--bisect` produce the same result. (Monotonous means that when moving away from head, the test result changes only once from "fail" to "ok".) If failure is not monotonous, any one of the patches that break the test is found at random.

If the test command returns an exit code of 125, the repository state is treated as "untestable" - for example you might get it to do this for a build break or other result that isn't the actual problem you want to track down. This can lead to multiple patches being reported as the source of the failure.

For example, if patch 1 introduces a build break, patch 2 breaks a test in an unrelated bit of the code, and patch 3 fixes the build break, then patches 1,2 and 3 would be identified as causing the failure.

The `--shrink-failures` option, on by default, adds a post-processing step to reorder patches to try to narrow down a failure more precisely. In the example above, it's likely that patch 2 could be moved before patch 1 or after patch 3, allowing it to be identified as the sole cause of the failure.

This shrinking can be disabled with `--no-shrink-failures`.

The `darcs revert` command discards unrecorded changes in the working tree. As with `darcs record`, you will be asked which hunks (changes) to revert. The `--all` switch can be used to avoid such prompting. If files or directories are specified, other parts of the working tree are not reverted.

In you accidentally reverted something you wanted to keep (for example, typing `darcs rev -a` instead of `darcs rec -a`), you can immediately run `darcs unrevert` to restore it. This is only guaranteed to work if the repository has not changed since `darcs revert` ran.

Unrevert is a rescue command in case you accidentally reverted something you wanted to keep (for example, typing `darcs rev -a` instead of `darcs rec -a`).

This command may fail if the repository has changed since the revert took place. Darcs will ask for confirmation before executing an interactive command that will DEFINITELY prevent unreversion.

Amend updates a "draft" patch with additions or improvements, resulting in a single "finished" patch.

By default `amend` proposes you to record additional changes. If instead you want to remove changes, use the flag `--unrecord`.

When recording a draft patch, it is a good idea to start the name with `DRAFT:`. When done, remove it with `darcs amend --edit-long-comment`. Alternatively, to change the patch name without starting an editor, use the `--name`/`-m` flag:

darcs amend --match 'name "DRAFT: foo"' --name 'foo2'

Like `darcs record`, if you call amend with files as arguments, you will only be asked about changes to those files. So to amend a patch to foo.c with improvements in bar.c, you would run:

darcs amend --match 'touch foo.c' bar.c

Note that this command edits the history of your repo. It is primarily intended to be used on patches that you authored yourself and did not yet publish. Using it for patches that are already published, or even ones you did not author yourself, may cause confusion and can disrupt your own and other people's work-flow. This depends a lot on how your project is organized, though, so there may be valid exceptions to this rule.

Using the `--not-in-remote` option is a good way to guard against accidentally editing published patches. Without arguments, this deselects any patches that are also present in the `defaultrepo`. If you work in a clone of some publically hosted repository, then your `defaultrepo` will be that public repo. You can also give the option an argument which is a path or URL of some other repository; you can use the option multiple times with different repositories, which has the effect of treating all of them as "upstream", that is, it prevents you from selecting a patch that is contained in any of these repos.

You can also guard only against editing another developer's patch by using an appropriate `--match` option with the `author` keyword. For instance, you could add something like `<cmd> match Your Name` to your `~/.darcs/defaults`.

The `darcs rebase' command is used to edit a collection of darcs patches.

The basic idea is that you can suspend patches from the end of a repository. These patches are no longer part of the history and have no effect on the working tree. Suspended patches are invisible to commands that access the repository from the outside, such as push, pull, clone, send, etc.

The sequence of suspended patches can be manipulated in ways that are not allowed for normal patches. For instance, `darcs rebase obliterate` allows you to remove a patch in this sequence, even if other suspended patches depend on it. These other patches will as a result become conflicted.

You can also operate on the normal patches in the usual way. If you add or remove normal patches, the suspended patches will be automatically adapted to still apply to the pristine state, possibly becoming conflicted in the course.

Note that as soon as a patch gets suspended, it will irrevocably loose its identity. This means that suspending a patch is subject to the usual warnings about editing the history of your project.

The opposite of suspending a patch is to unsuspend it. This turns it back into a normal patch. If the patch is conflicted as a result of previous operations on either the normal patches or the suspended patches, unsuspending will create appropriate conflict markup. Note, however, that the unsuspended patch itself WILL NOT BE CONFLICTED itself. This means that there is no way to re-generate the conflict markup. Once you removed it, by editing files or using `darcs revert`, any information about the conflict is lost.

As long as you have suspended patches, darcs will display a short message after each command to remind you that your patch editing operation is still in progress.

Copy and apply patches from another repository, suspending any local patches that conflict.

Apply a patch bundle, suspending any local patches that conflict.

Select patches to move into a suspended state at the end of the repo.

Note that this command edits the history of your repo. It is primarily intended to be used on patches that you authored yourself and did not yet publish. Using it for patches that are already published, or even ones you did not author yourself, may cause confusion and can disrupt your own and other people's work-flow. This depends a lot on how your project is organized, though, so there may be valid exceptions to this rule.

Using the `--not-in-remote` option is a good way to guard against accidentally editing published patches. Without arguments, this deselects any patches that are also present in the `defaultrepo`. If you work in a clone of some publically hosted repository, then your `defaultrepo` will be that public repo. You can also give the option an argument which is a path or URL of some other repository; you can use the option multiple times with different repositories, which has the effect of treating all of them as "upstream", that is, it prevents you from selecting a patch that is contained in any of these repos.

You can also guard only against editing another developer's patch by using an appropriate `--match` option with the `author` keyword. For instance, you could add something like `<cmd> match Your Name` to your `~/.darcs/defaults`.

Select suspended patches to restore to the end of the repo.

Edit suspended patches.

Obliterate a patch that is currently suspended.

List the currently suspended changes.

Upgrade a repo with an old-style rebase in progress.

Doing this means you won't be able to use darcs version < 2.15 with this repository until the rebase is finished.

Rollback is used to undo the effects of some changes from patches in the repository. The selected changes are undone in your working tree, but the repository is left unchanged. First you are offered a choice of which patches to undo, then which changes within the patches to undo.

Before doing `rollback`, you may want to temporarily undo the changes of your working tree (if there are) and save them for later use. To do so, you can run `revert`, then run `rollback`, record a patch, and run `unrevert` to restore the saved changes into your working tree.

Unrecord does the opposite of record: it deletes patches from the repository without changing the working tree. The changes are now again visible with `darcs whatsnew` and you can record or revert them as you please.

Note that this command edits the history of your repo. It is primarily intended to be used on patches that you authored yourself and did not yet publish. Using it for patches that are already published, or even ones you did not author yourself, may cause confusion and can disrupt your own and other people's work-flow. This depends a lot on how your project is organized, though, so there may be valid exceptions to this rule.

Using the `--not-in-remote` option is a good way to guard against accidentally editing published patches. Without arguments, this deselects any patches that are also present in the `defaultrepo`. If you work in a clone of some publically hosted repository, then your `defaultrepo` will be that public repo. You can also give the option an argument which is a path or URL of some other repository; you can use the option multiple times with different repositories, which has the effect of treating all of them as "upstream", that is, it prevents you from selecting a patch that is contained in any of these repos.

You can also guard only against editing another developer's patch by using an appropriate `--match` option with the `author` keyword. For instance, you could add something like `<cmd> match Your Name` to your `~/.darcs/defaults`.

Obliterate completely removes recorded patches from your local repository. The changes will be undone in your working tree and the patches will not be shown in your changes list anymore. Beware that you can lose precious code by obliterating!

One way to save obliterated patches is to use the -O flag. A patch bundle will be created locally, that you will be able to apply later to your repository with `darcs apply`. See `darcs send` for a more detailed description.

Note that this command edits the history of your repo. It is primarily intended to be used on patches that you authored yourself and did not yet publish. Using it for patches that are already published, or even ones you did not author yourself, may cause confusion and can disrupt your own and other people's work-flow. This depends a lot on how your project is organized, though, so there may be valid exceptions to this rule.

Using the `--not-in-remote` option is a good way to guard against accidentally editing published patches. Without arguments, this deselects any patches that are also present in the `defaultrepo`. If you work in a clone of some publically hosted repository, then your `defaultrepo` will be that public repo. You can also give the option an argument which is a path or URL of some other repository; you can use the option multiple times with different repositories, which has the effect of treating all of them as "upstream", that is, it prevents you from selecting a patch that is contained in any of these repos.

You can also guard only against editing another developer's patch by using an appropriate `--match` option with the `author` keyword. For instance, you could add something like `<cmd> match Your Name` to your `~/.darcs/defaults`.

Remove unrecorded changes from the working tree.

This is an alias for `darcs revert -l/--look-for-adds` which means it works also on files that have not been added. You can additionally pass `--boring` to get rid of *every* unrecorded file or directory.

See description of `darcs revert` for more details.

The `darcs tag` command names the current repository state, so that it can easily be referred to later. It does so by recording a special kind of patch that makes no changes and which explicitly depends on all patches currently existing in the repository (except for those which are depended upon by other tags already in the repository). In the common case of a sequential series of tags, this means that the tag depends on all patches since the last tag, plus that tag itself.

Every *important* state should be tagged; in particular it is good practice to tag each stable release with a number or codename. Advice on release numbering can be found at <http://producingoss.com/en/development-cycle.html>.

To reproduce the state of a repository `R` as at tag `t`, use the command `darcs clone --tag t R`. Note however that tags are matched as regular expressions, like with `--patch`. To make sure you get the right tag it may be better to use `darcs clone --tag '^t$'`. The command `darcs show tags` lists all tags in the current repository.

Tagging also provides significant performance benefits: when Darcs reaches a tag that depends on all preceding patches, it can often stop processing. A tag in such a position is called "clean". For instance, operations like push and pull need to examine only patches that come after the latest shared clean tag.

Like normal patches, a tag has a name, an author, a timestamp and an optional long description, but it does not change the working tree. A tag can have any name, but it is generally best to pick a naming scheme and stick to it.

By default a tag names the entire repository state at the time the tag is created. If the --ask-deps option is used, the patches to include as part of the tag can be explicitly selected.

The `darcs tag` command accepts the `--pipe` option, which behaves as described in `darcs record`.

When working on project with multiple repositories and contributors, it is sometimes desirable for a preference to be set consistently project-wide. This is achieved by treating a preference set with `darcs setpref` as an unrecorded change, which can then be recorded and then treated like any other patch.

Valid preferences are:

* test -- a shell command that runs regression tests * predist -- a shell command to run before `darcs dist' * boringfile -- the path to a version-controlled boring file * binariesfile -- the path to a version-controlled binaries file

For example, a project using GNU autotools, with a `make test` target to perform regression tests, might enable Darcs' integrated regression testing with the following command:

darcs setpref test 'autoconf && ./configure && make && make test'

Note that merging is not currently implemented for preferences: if two patches attempt to set the same preference, the last patch applied to the repository will always take precedence. This is considered a low-priority bug, because preferences are seldom set.

Send is used to prepare a bundle of patches that can be applied to a target repository. Send accepts the URL of the repository as an argument. When called without an argument, send will use the most recent repository that was either pushed to, pulled from or sent to. By default, the patch bundle is saved to a file, although you may directly send it by mail.

The `--output`, `--output-auto-name`, and `--to` flags determine what darcs does with the patch bundle after creating it. If you provide an `--output` argument, the patch bundle is saved to that file. If you specify `--output-auto-name`, the patch bundle is saved to a file with an automatically generated name. If you give one or more `--to` arguments, the bundle of patches is sent to those locations. The locations may either be email addresses or urls that the patch should be submitted to via HTTP.

If you provide the `--mail` flag, darcs will look at the contents of the `_darcs/prefs/email` file in the target repository (if it exists), and send the patch by email to that address. In this case, you may use the `--cc` option to specify additional recipients without overriding the default repository email address.

If `_darcs/prefs/post` exists in the target repository, darcs will upload to the URL contained in that file, which may either be a `mailto:` URL, or an `http://` URL. In the latter case, the patch is posted to that URL.

If there is no email address associated with the repository, darcs will prompt you for an email address.

Use the `--subject` flag to set the subject of the e-mail to be sent. If you don't provide a subject on the command line, darcs will make one up based on names of the patches in the patch bundle.

Use the `--in-reply-to` flag to set the In-Reply-To and References headers of the e-mail to be sent. By default no additional headers are included so e-mail will not be treated as reply by mail readers.

If you want to include a description or explanation along with the bundle of patches, you need to specify the `--edit-description` flag, which will cause darcs to open up an editor with which you can compose a message to go along with your patches.

If you want to use a command different from the default one for sending email, you need to specify a command line with the `--sendmail-command` option. The command line can contain some format specifiers which are replaced by the actual values. Accepted format specifiers are `%s` for subject, `%t` for to, `%c` for cc, `%b` for the body of the mail, `%f` for from, `%a` for the patch bundle and the same specifiers in uppercase for the URL-encoded values. Additionally you can add `%<` to the end of the command line if the command expects the complete email message on standard input. E.g. the command lines for evolution and msmtp look like this:

evolution "mailto:%T?subject=%S&attach=%A&cc=%C&body=%B"
msmtp -t %<

Do not confuse the `--author` options with the return address that `darcs send` will set for your patch bundle.

For example, if you have two email addresses A and B:

* If you use `--author A` but your machine is configured to send
mail from address B by default, then the return address on your
message will be B.
* If you use `--from A` and your mail client supports setting the
From: address arbitrarily (some non-Unix-like mail clients,
especially, may not support this), then the return address will
be A; if it does not support this, then the return address will
be B.
* If you supply neither `--from` nor `--author` then the return
address will be B.

In addition, unless you specify the sendmail command with `--sendmail-command`, darcs sends email using the default email command on your computer. This default command is determined by the `configure` script. Thus, on some non-Unix-like OSes, `--from` is likely to not work at all.

The --inherit-default option is meant to support a work flow where you have different branches of the same upstream repository and want all your branches to have the same upstream repo as the defaultrepo. It is most useful when enabled globally by adding 'ALL --inherit-default' to your ~/darcs/defaults file.

For the commands push, pull, and send it means the following: Changes the meaning of the --set-default option so that it sets the (local) defaultrepo to the defaultrepo of the remote repo, instead of the remote repo itself. This happens only if the remote repo does have a defaultrepo set and both local and remote repositories are locally valid paths on the same host, otherwise fall back to the default behavior (--no-inherit-default).

The `darcs apply` command takes a patch bundle and attempts to insert it into the current repository. In addition to invoking it directly on bundles created by `darcs send`, it is used internally by `darcs push` on the remote end of an SSH connection.

If no file is supplied, the bundle is read from standard input.

If given an email instead of a patch bundle, Darcs will look for the bundle as a MIME attachment to that email. Currently this will fail if the MIME boundary is rewritten, such as in Courier and Mail.app.

If gpg(1) is installed, you can use `--verify pubring.gpg` to reject bundles that aren't signed by a key in `pubring.gpg`.

If `--test` is supplied and a test is defined (see `darcs setpref`), the bundle will be rejected if the test fails after applying it.

Unlike most Darcs commands, `darcs apply` defaults to `--all`. Use the `--interactive` option to pick which patches to apply from a bundle.

A patch bundle may introduce unresolved conflicts with existing patches or with the working tree. By default, Darcs will refuse to apply conflicting patches (`--no-allow-conflicts`).

The `--mark-conflicts` option instructs Darcs to allow conflicts and try to add conflict markup in your working tree. Note that this may (partly) fail, because some conflicts cannot be marked, such as e.g. conflicts between two adds of the same file. In this case Darcs will warn you and display the conflicting changes instead. When Darcs detects conflicts with unrecorded changes, it will give you an extra warning and prompts you to confirm that you want to continue. This is because your original unrecorded changes cannot be automatically restored by Darcs.

Note that conflict markup is something Darcs adds to your working tree files. Nevertheless, you can always re-construct it using `darcs mark-conflicts`.

The `--external-merge` option lets you resolve conflicts using an external merge tool. In the option, `%a` is replaced with the common ancestor (merge base), `%1` with the first version, `%2` with the second version, and `%o` with the path where your resolved content should go. For example, to use the xxdiff visual merge tool you'd specify: `--external-merge='xxdiff -m -O -M %o %1 %a %2'`

The `--allow-conflicts` option allows conflicts but does not add conflict markup. This is useful when you want to treat a repository as just a bunch of patches, such as using `darcs pull --union` to download all of your co-workers' patches before going offline. Again, conflict markup can be added at any time later on using `darcs mark-conflicts`.

For more information on conflicts in Darcs and how to resolve them, see the help on `darcs mark-conflicts`.

The `darcs optimize` command modifies internal data structures of the current repository in an attempt to reduce its resource requirements.

For further details see the descriptions of the subcommands.

Darcs normally does not delete hashed files that are no longer referenced by the current repository state. This command can be use to get rid of these files to save some disk space.

Using this option creates 'repository packs' that can dramatically speed up performance when a user does a `darcs clone` of the repository over HTTP. To make use of packs, the clients must have a darcs of at least version 2.10.

This command moves recent patches (those not included in the latest tag) to the "front", reducing the amount that a typical remote command needs to download. It should also reduce the CPU time needed for some operations. This is the behavior with --shallow which is the default.

With the --deep option it tries to optimize all tags in the whole repository. This breaks the history of patches into smaller bunches, which can further improve efficiency, but requires all patches to be present. It is therefore less suitable for lazy clones.

Build the patch index, an internal data structure that accelerates commands that need to know what patches touch a given file. Such as annotate and log.

Delete and stop maintaining the patch index from the repository.

Patches, inventories, and pristine files are compressed with zlib (RFC 1951) to reduce storage (and download) size. Older darcs versions allowed to store them uncompressed, and darcs is still able to read those files if they are not compressed.

The `darcs optimize uncompress` and `darcs optimize compress` commands can be used to ensure existing patches in the current repository are respectively uncompressed or compressed.

Patches, inventories, and pristine files are compressed with zlib (RFC 1951) to reduce storage (and download) size. Older darcs versions allowed to store them uncompressed, and darcs is still able to read those files if they are not compressed.

The `darcs optimize uncompress` and `darcs optimize compress` commands can be used to ensure existing patches in the current repository are respectively uncompressed or compressed.

The `darcs optimize relink` command hard-links patches that the current repository has in common with its peers. Peers are those repositories listed in `_darcs/prefs/sources`, or defined with the `--sibling` option (which can be used multiple times).

Darcs uses hard-links automatically, so this command is rarely needed. It is most useful if you used `cp -r` instead of `darcs clone` to copy a repository, or if you pulled the same patch from a remote repository into multiple local repositories.

Convert old-fashioned repositories to the current default hashed format.

This command deletes obsolete files within the global cache.

It also automatically migrates the global cache to the (default) bucketed format.

`darcs dist` creates a compressed archive in the repository's root directory, containing the recorded state of the working tree (unrecorded changes and the `_darcs` directory are excluded). The command accepts matchers to create an archive of some past repository state, for instance `--tag`.

By default, the archive (and the top-level directory within the archive) has the same name as the repository, but this can be overridden with the `--dist-name` option.

If a predist command is set (see `darcs setpref`), that command will be run on the recorded state prior to archiving. For example, autotools projects would set it to `autoconf && automake`.

If `--zip` is used, matchers and the predist command are ignored.

Darcs requires human guidance to reconcile independent changes to the same part of a file. When a conflict first occurs, darcs will add the initial state and all conflicting choices to the working tree, delimited by the markers `v v v`, `=====`, `* * *` and `^ ^ ^`, as follows:

v v v v v v v
initial state
=============
first choice
*************
...more choices...
*************
last choice
^ ^ ^ ^ ^ ^ ^

If you happened to revert or manually delete this conflict markup without actually resolving the conflict, `darcs mark-conflicts` can be used to re-create it; and similarly if you have used `darcs apply` or `darcs pull` with `--allow-conflicts`, where conflicts aren't marked initially.

In Darcs, a conflict counts as resolved when all of the changes involved in the conflict (which can be more than two) are depended on by one or more later patches. If you record a resolution for a particular conflict, `darcs mark-conflicts` will no longer mark it, indicating that it is resolved. If you have unrecorded changes, these count as (potential) conflict resolutions, too, just as if you had already recorded them.

This principle extends to explicit "semantic" dependencies. For instance, recording a tag will automatically mark all conflicts as resolved.

In the above schematic example the "initial state" corresponds to the recorded state of the file in your repository. That is to say, the recorded effect of a conflict is to apply none of the conflicting changes. This is usually not a state you would regard as a successful resolution of the conflict; but there are exceptional situations where this may be exactly what you want. In order to tell Darcs that you want this conflict to be regarded as resolved, use `darcs record --ask-deps` to record a patch that explicitly depends on all patches involved in the conflict.

The `darcs repair` command attempts to fix corruption in the current repository. It works by successively applying all patches in the repository to an empty tree, each time checking that the patch can be cleanly applied to the current pristine tree. If we detect a problem, we try to repair the patch. Finally we compare the existing pristine with the newly reconstructed one and if they differ, replace the existing one. Any problem encountered is reported. The flag `--dry-run` makes this operation read-only and causes it to exit unsuccessfully (with a non-zero exit status) in case any problems are enountered.

Convert repositories between various formats.

See description of the subcommands for details.

This command converts a repository that uses the old patch semantics `darcs-1` to a new repository with current `darcs-2` semantics.

WARNING: the repository produced by this command is not understood by Darcs 1.x, and patches cannot be exchanged between repositories in darcs-1 and darcs-2 formats. Also, you should not exchange patches between repositories created by different invocations of this command. This means: - Before doing this conversion, you should merge into this repo any patches
existing elsewhere that you might want to merge in future, so that they
will remain mergeable. (You can always remove them again after converting). - After converting, you should tell everyone with a fork of this repo
to discard it and make a new fork of the converted repo.

Initialize and clone commands create the preferences files in _darcs/prefs/ directory of the newly created repository. With option --with-prefs-templates `boring` and `binaries` preferences files will be filled with default templates. If you want to leave these files empty use --no-prefs-templates option. If you prefer to keep the relevant settings globally, it will be convenient to add 'ALL no-prefs-templates' to your ~/darcs/defaults file.

This command enables you to export darcs repositories into git.

For a one-time export you can use the recipe:

$ cd repo
$ git init ../mirror
$ darcs convert export | (cd ../mirror && git fast-import)

For incremental export using marksfiles:

$ cd repo
$ git init ../mirror
$ touch ../mirror/git.marks
$ darcs convert export --read-marks darcs.marks --write-marks darcs.marks
| (cd ../mirror && git fast-import --import-marks=git.marks --export-marks=git.marks)

In the case of incremental export, be careful to never amend, delete or reorder patches in the source darcs repository.

Also, be aware that exporting a darcs repo to git will not be exactly faithful in terms of history if the darcs repository contains conflicts.

Limitations:

* Empty directories are not supported by the fast-export protocol.
* Unicode filenames are currently not correctly handled.
See http://bugs.darcs.net/issue2359 .

This command imports git repositories into new darcs repositories. Further options are accepted (see `darcs help init`).

To convert a git repo to a new darcs one you may run:

$ (cd gitrepo && git fast-export --all -M) | darcs convert import darcsmirror

WARNING: git repositories with branches will produce weird results,
use at your own risks.

Incremental import with marksfiles is currently not supported.

Initialize and clone commands create the preferences files in _darcs/prefs/ directory of the newly created repository. With option --with-prefs-templates `boring` and `binaries` preferences files will be filled with default templates. If you want to leave these files empty use --no-prefs-templates option. If you prefer to keep the relevant settings globally, it will be convenient to add 'ALL no-prefs-templates' to your ~/darcs/defaults file.

Fetch is similar to `pull` except that it does not apply any patches to the current repository. Instead, it generates a patch bundle that you can apply later with `apply`.

Fetch's behaviour is essentially similar to pull's, so please consult the help of `pull` to know more.