Patterns Specification
Description
Different pattern matching rules for arguments in *-spec form are defined
for operation with each entity type in DNF5. In this section all rules are
described and explained in detail, with examples.
Globs
Pattern specification supports the same glob pattern matching that shell does. The following patterns are supported:
*Matches any number of characters.
?Matches any single character.
[]Matches any one of the enclosed characters. A pair of characters separated by a hyphen denotes a range expression; any character that falls between those two characters, inclusive, is matched. If the first character following the
[is a!or a^then any character not enclosed is matched.
Note: Curly brackets ({}) are not supported. You can still use them in
shells that support them and let the shell do the expansion, but if quoted or
escaped, DNF5 will not expand them.
Packages
Many commands take a <package-spec*> parameter that selects a package for
the operation. Depending on the command the <package-spec*> argument is
matched against:
NEVRA [N] or case Insentive NEVRA [NI]
Provides [P]
sequentially until a match is found.
For example <package-spec-NP> is first matched againts NEVRAs and if no
matching NEVRA is found it is matched againts Provides.
When <package-spec> is a package name or a provide, the user can provide
additional restriction rules for matching the arguments. Basic version comparisons
can be used for this purpose (=, >, <, >=, <=), like this <package-spec> >= <version>,
where the <version> argument is in a [EPOCH:]VERSION[-RELEASE] format
as specified in the NEVRA matching section.
To build more complex expressions, a rich dependency feature
is also supported, which is always enclosed in parentheses. Boolean
operators and nesting can be used, f.e. (<spec1> or (<spec2> and <spec3>)).
For more information, please see RPM boolean dependencies.
NEVRA matching
Each package can be uniquely identified by the NEVRA string. It consists of 5 parts of information:
- Name
- Package name.
- Epoch
- Epoch number.It is not always included.
The epoch number overrides other version checking, so it can be used to force the package upgrade over some other one.
- Version
- Version string.It is not strictly numeric.It is intended to match the upstream software version.
- Release
- Edition string.
It is an information about the particular package build, usually a number increased with the newer build. It is not connected with the upstream software.
- Architecture
- Target architecture string.Defines the processor type the package is intended to be installed on.
It can be also a package containing source files (
src) or architecture-independent package (noarch).
When matching against NEVRAs, partial matching is supported. DNF5 tries to match
the spec against the following list of NEVRA forms (in decreasing order of
priority):
NAME-[EPOCH:]VERSION-RELEASE.ARCHNAME.ARCHNAMENAME-[EPOCH:]VERSION-RELEASENAME-[EPOCH:]VERSION
Note that name can in general contain dashes (e.g. package-with-dashes).
The first form that matches any packages is used and the remaining forms are
not tried. If none of the forms match any packages, an attempt is made to match
the <package-spec> against full package NEVRAs. This is only relevant
if globs are present in the <package-spec>.
You can specify globs as part of any of the five NEVRA components. You can also specify a glob pattern to match over multiple NEVRA components (in other words, to match across the NEVRA separators). In that case, however, you need to write the spec to match against full package NEVRAs, as it is not possible to split such spec into NEVRA forms.
File Provides matching
If a spec starts with either / or */, it is considered as a potential file provide.
Binaries matching
Whether to consider package binaries during matching.
Checks if given spec is a binary in /usr/bin/ or /usr/sbin/.
Comps
<group-spec>``|``<environment-spec> allows one to select groups|environments a particular
operation should work on. It is a case insensitive string (supporting globbing characters) that
is matched against a group’s|environment’s ID, canonical name and name translated into the
current LC_MESSAGES locale (if possible).
Comps specs are prefixed by @ for commands that also accept package specs.
For example see dnf5-install(8), Install Command.
Modules
<module-spec> allows one to select modules or profiles a particular operation should work
on.
Since NEVRA matching form is insufficient for modules, they are uniquely identified by the
NSVCA format (NAME:STREAM:VERSION:CONTEXT:ARCH/PROFILE). Supported partial forms are the following:
NAMENAME:STREAMNAME:STREAM:VERSIONNAME:STREAM:VERSION:CONTEXTAll above combinations with::ARCH(e.g.NAME::ARCH)NAME:STREAM:VERSION:CONTEXT:ARCHAll above combinations with/PROFILE(e.g.NAME/PROFILE)
In case stream is not specified, the enabled or the default stream is used, in this order. In case profile is not specified, the system default profile or the ‘default’ profile is used.
Transactions
<transaction-spec> can be in one of several forms. If it is an integer, it
specifies a transaction ID. Specifying last is the same as specifying the ID
of the most recent transaction. The last form is last-<offset>, where
<offset> is a positive integer. It specifies offset-th transaction preceding
the most recent transaction.
See Also
- RPM boolean dependencies: