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File Name Glob Patterns
A glob pattern is a text expression that matches one or more
file names using wild cards familiar to most users of a command line.
* is a glob that matches any name at all and
Readme.txt is a glob that matches exactly one file.
Note that although both are notations for describing patterns in text, glob patterns are not the same thing as a regular expression or regexp.
A number of fossil setting values hold one or more file glob patterns that will identify files needing special treatment. Glob patterns are also accepted in options to certain commands as well as query parameters to certain pages.
In many cases more than one glob may be specified in a setting, option, or query parameter by listing multiple globs separated by a comma or white space.
Of course, many fossil commands also accept lists of files to act on, and those also may be specified with globs. Although those glob patterns are similar to what is described here, they are not defined by fossil, but rather by the conventions of the operating system in use.
A list of glob patterns is simply one or more glob patterns separated by white space or commas. If a glob must contain white spaces or commas, it can be quoted with either single or double quotation marks. A list is said to match if any one (or more) globs in the list matches.
A glob pattern is a collection of characters compared to a target text, usually a file name. The whole glob is said to match if it successfully consumes and matches the entire target text. Glob patterns are made up of ordinary characters and special characters.
Ordinary characters consume a single character of the target and must match it exactly.
Special characters (and special character sequences) consume zero or more characters from the target and describe what matches. The special characters (and sequences) are:
||Matches any sequence of zero or more characters|
||Matches exactly one character|
||Matches one character from the enclosed list of characters|
||Matches one character not in the enclosed list|
Special character sequences have some additional features:
- A range of characters may be specified with
[a-d]matches exactly the same characters as
[abcd]. Ranges reflect Unicode code points without any locale-specific collation sequence.
-in a list by placing it last, just before the
]in a list by making the first character after the
[^. At any other place,
]ends the list.
^in a list by placing anywhere except first after the
- Beware that ranges in lists may include more than you expect:
Z, but also matches
aand some less obvious characters such as
]with code point values between
- Beware that a range must be specified from low value to high
[z-a]does not match any character at all, preventing the entire glob from matching.
- Note that unlike typical Unix shell globs, wildcards (
?, and character lists) are allowed to match
/directory separators as well as the initial
.in the name of a hidden file or directory.
Some examples of character lists:
||Matches any one of
||Matches exactly one character other than
||Matches exactly one hexadecimal digit|
||Matches exactly one character other than
||Matches exactly one character other than
White space means the specific ASCII characters TAB, LF, VT, FF, CR, and SPACE. Note that this does not include any of the many additional spacing characters available in Unicode, and specifically does not include U+00A0 NO-BREAK SPACE.
Because both LF and CR are white space and leading and trailing spaces are stripped from each glob in a list, a list of globs may be broken into lines between globs when the list is stored in a file (as for a versioned setting).
Similarly 'single quotes' and "double quotes" are the ASCII straight quote characters, not any of the other quotation marks provided in Unicode and specifically not the "curly" quotes preferred by typesetters and word processors.
File Names to Match
Before it is compared to a glob pattern, each file name is transformed to a canonical form. The glob must match the entire canonical file name to be considered a match.
The canonical name of a file has all directory separators changed to
/, redundant slashes are removed, all
. path components are
removed, and all
.. path components are resolved. (There are
additional details we are ignoring here, but they cover rare edge
cases and also follow the principle of least surprise.)
The goal is to have a name that is the simplest possible for each particular file, and that will be the same on Windows, Unix, and any other platform where fossil is run.
Beware, however, that all glob matching is case sensitive. This will
not be a surprise on Unix where all file names are also case
sensitive. However, most Windows file systems are case preserving and
case insensitive. That is, on Windows, the names
are names of the same file; on Unix they are different files.
Some example cases:
||Matches only a file named
||Matches every C source or header file in the tree at the root or at any depth. Again, this is (deliberately) different from Unix file globs and Windows wild cards.|
Where Globs are Used
Settings that are Globs
These settings are all lists of glob patterns:
||Files that should be treated as binary files for committing and merging purposes|
||Files that the
||Files in which it is okay to have
||Alias for the
||Files that the
||Files that the
||Files that the
All may be versioned, local, or global. Use
settings to manage local and global settings, or a file in the
.fossil-settings/ folder at the root of the tree named
for each for versioned setting.
Using versioned settings for these not only has the advantage that they are tracked in the repository just like the rest of your project, but you can more easily keep longer lists of more complicated glob patterns than would be practical in either local or global settings.
ignore-glob is an example of one setting that frequently grows
to be an elaborate list of files that should be ignored by most
commands. This is especially true when one (or more) IDEs are used in
a project because each IDE has its own ideas of how and where to cache
information that speeds up its browsing and building tasks but which
need not be preserved in your project's history.
Commands that Refer to Globs
Many of the commands that respect the settings containing globs have
options to override some or all of the settings. These options are
usually named to correspond to the setting they override, such as
--ignore to override the
ignore-glob setting. These commands are:
zip produce compressed archives of a
specific checkin. They may be further restricted by options that
specify glob patterns that name files to include or exclude rather
than archiving the entire checkin.
implement or support with web servers provide a mechanism to name some
files to serve with static content where a list of glob patterns
specifies what content may be served.
Web Pages that Refer to Globs
/timeline page supports the query parameter
names a list of glob patterns defining which files to focus the
timeline on. It also has the query parameters
names a tag to focus on, which can be configured with
use a glob pattern to match tag names instead of the default exact
match or a couple of other comparison styles.
/zip generate compressed archives
of a specific checkin. They may be further restricted by query
parameters that specify glob patterns that name files to include or
exclude rather than taking the entire checkin.
Fossil glob patterns are based on the glob pattern feature of POSIX
shells. Fossil glob patterns also have a quoting mechanism, discussed
above. Because other parts of your operating system may interpret glob
patterns and quotes separately from Fossil, it is often difficult to
give glob patterns correctly to Fossil on the command line. Quotes and
special characters in glob patterns are likely to be interpreted when
given as part of a
fossil command, causing unexpected behavior.
These problems do not affect versioned settings files
or Admin → Settings in Fossil UI. Consequently, it is better to
*-glob settings via these methods than to use
That advice does not help you when you are giving one-off glob patterns
fossil commands. The remainder of this section gives remedies and
workarounds for these problems.
If you are using Fossil on a system with a POSIX-compatible shell
— Linux, macOS, the BSDs, Unix, Cygwin, WSL etc. — the shell
may expand the glob patterns before passing the result to the
Sometimes this is exactly what you want. Consider this command for example:
$ fossil add RE*
If you give that command in a directory containing
RELEASE-NOTES.txt, the shell will expand the command to:
$ fossil add README.txt RELEASE-NOTES.txt
…which is compatible with the
fossil add command's argument list,
which allows multiple files.
Now consider what happens instead if you say:
$ fossil add --ignore RE* src/*.c
This does not do what you want because the shell will expand both
src/*.c, causing one of the two files matching the
pattern to be ignored and the other to be added to the repository. You
need to say this in that case:
$ fossil add --ignore 'RE*' src/*.c
The single quotes force a POSIX shell to pass the
RE* glob pattern
through to Fossil untouched, which will do its own glob pattern
matching. There are other methods of quoting a glob pattern or escaping
its special characters; see your shell's manual.
Beware that Fossil's
--ignore option does not override explicit file
$ fossil add --ignore 'REALLY SECRET STUFF.txt' RE*
You might think that would add everything beginning with
REALLY SECRET STUFF.txt, but when a file is both given
explicitly to Fossil and also matches an ignore rule, Fossil asks what
you want to do with it in the default case; and it does not even ask
if you gave the
--force option along with
The spaces in the ignored file name above bring us to another point: such file names must be quoted in Fossil glob patterns, lest Fossil interpret it as multiple glob patterns, but the shell interprets quotation marks itself.
One way to fix both this and the previous problem is:
$ fossil add --ignore "'REALLY SECRET STUFF.txt'" READ*
The nested quotation marks cause the inner set to be passed through to
Fossil, and the more specific glob pattern at the end — that is,
RE* — avoids a conflict between explicitly-listed
--ignore rules in the
fossil add command.
Another solution would be to use shell escaping instead of nested quoting:
$ fossil add --ignore "\"REALLY SECRET STUFF.txt\"" READ*
It bears repeating that the two glob patterns here are not interpreted
the same way when running this command from a subdirectory of the top
checkout directory as when running it at the top of the checkout tree.
If these files were in a subdirectory of the checkout tree called
and that was your current working directory, the command would have to
$ fossil add --ignore "'doc/REALLY SECRET STUFF.txt'" READ*
instead. The Fossil glob pattern still needs the
doc/ prefix because
Fossil always interprets glob patterns from the base of the checkout
directory, not from the current working directory as POSIX shells do.
When in doubt, use
fossil status after running commands like the
above to make sure the right set of files were scheduled for insertion
into the repository before checking the changes in. You never want to
accidentally check something like a password, an API key, or the
private half of a public cryptographic key into Fossil repository that
can be read by people who should not have such secrets.
Neither standard Windows command shell —
cmd.exe or PowerShell
— expands glob patterns the way POSIX shells do. Windows command
shells rely on the command itself to do the glob pattern expansion. The
way this works depends on several factors:
- the version of Windows you are using
- which OS upgrades have been applied to it
- the compiler that built your Fossil executable
- whether you are running the command interactively
- whether the command is built against a runtime system that does this at all
- whether the Fossil command is being run from a file named
*.BATvs being named
These factors also affect how a program like
quotation marks on its command line.
The fifth item above does not apply to
fossil.exe when built with
typical tool chains, but we will see an example below where the exception
applies in a way that affects how Fossil interprets the glob pattern.
The most common problem is figuring out how to get a glob pattern passed
on the command line into
fossil.exe without it being expanded by the C
runtime library that your particular Fossil executable is linked to,
which tries to act like the POSIX systems described above. Windows is
not strongly governed by POSIX, so it has not historically hewed closely
to its strictures.
(This section does not cover the Microsoft POSIX subsystem, Windows' obsolete Services for Unix 3.x feature, or the Windows Subsystem for Linux. (The latter is sometimes incorrectly called "Bash on Windows" or "Ubuntu on Windows.") See the POSIX Systems section above for those cases.)
For example, consider how you would set
* in order to
disable Fossil's "looks like a binary file" checks. The naïve
approach will not work:
C:\...> fossil setting crlf-glob *
The C runtime library will expand that to the list of all files in the current directory, which will probably cause a Fossil error because Fossil expects either nothing or option flags after the setting's new value.
Let's try again:
C:\...> fossil setting crlf-glob '*'
That may or may not work. Either
* needs to be passed through
to Fossil untouched for this to do what you expect, which may or may not
happen, depending on the factors listed above.
An approach that will work reliably is:
C:\...> echo * | fossil setting crlf-glob --args -
This works because the built-in command
echo does not expand its
arguments, and the
--args - option makes it read further command
arguments from Fossil's standard input, which is connected to the output
echo by the pipe. (
- is a common Unix convention meaning
Another (usually) correct approach is:
C:\...> fossil setting crlf-glob *,
This works because the trailing comma prevents the command shell from
matching any files, unless you happen to have files named with a
trailing comma in the current directory. If the pattern matches no
files, it is passed into Fossil's
main() function as-is by the C
runtime system. Since Fossil uses commas to separate multiple glob
patterns, this means "all files at the root of the Fossil checkout
directory and nothing else."
Many other version control systems handle the specific case of ignoring certain files differently from fossil: they have you create individual "ignore" files in each folder, which specify things ignored in that folder and below. Usually some form of glob patterns are used in those files, but the details differ from fossil.
In many simple cases, you can just store a top level "ignore" file in
.fossil-settings/ignore-glob. But as usual, there will be lots of
Git has a rich collection of ignore files which accumulate rules that affect the current command. There are global files, per-user files, per workspace unmanaged files, and fully version controlled files. Some of the files used have no set name, but are called out in configuration files.
In contrast, fossil has a global setting and a local setting, but the local setting
overrides the global rather than extending it. Similarly, a fossil
--ignore option replaces the
ignore-glob setting rather
than extending it.
With that in mind, translating a
.gitignore file into
.fossil-settings/ignore-glob may be possible in many cases. Here are
some of features of
.gitignore and comments on how they relate to
- "A blank line matches no files..." is the same in fossil.
- "A line starting with # serves as a comment...." not in fossil.
- "Trailing spaces are ignored unless they are quoted..." is similar in fossil. All whitespace before and after a glob is trimmed in fossil unless quoted with single or double quotes. Git uses backslash quoting instead, which fossil does not.
- "An optional prefix "!" which negates the pattern..." not in fossil.
- Git's globs are relative to the location of the
.gitignorefile; fossil's globs are relative to the root of the workspace.
- Git's globs and fossil's globs treat directory separators differently. Git includes a notation for zero or more directories that is not needed in fossil.
In a project with source and documentation:
work +-- doc +-- src
doc/.gitignore might contain:
# Finished documents by pandoc via LaTeX *.pdf # Intermediate files *.tex *.toc *.log *.out *.tmp
.fossil-settings/ignore-glob with similar effect, also
limited to the
doc/*.pdf doc/*.tex, doc/*.toc, doc/*.log, doc/*.out, doc/*.tmp
Implementation and References
Most of the implementation of glob pattern handling in fossil is found
file.c, and each individual command and web page that uses
a glob pattern. Find commands and pages in the fossil sources by
looking for comments like
COMMAND: add or
WEBPAGE: timeline in
front of the function that implements the command or page in files
src/*.c. (Fossil's build system creates the tables used to dispatch
commands at build time by searching the sources for those comments.) A
few starting points:
||Implementation of glob pattern list loading, parsing, and matching.|
||Implementation of various kinds of canonical names of a file.|
The actual pattern matching is implemented in SQL, so the
GLOB and the other string matching operators in
SQLite is useful. Of
course, the SQLite source code
and test harnesses
also make entertaining reading.