declpac/PackageProvides.md

Checking if a Package is Provided by Another Package

Using FindDBSatisfier

The FindDBSatisfier method in the handle finds a package that satisfies a given dependency string across sync databases. It automatically resolves Provides relationships.

Basic Usage

// Given a package name "foo", find which package provides it
h := dyalpm.NewHandle(...)
dbs := h.SyncDBS()

// This finds ANY package that satisfies "foo" - including via Provides
provider := h.FindDBSatisfier(dbs, "foo")
if provider != nil {
    // The package "foo" is provided by provider.Name()
}

How It Works

When you search for a package "foo", ALPM will find packages that:

1. Are named "foo"
2. Have Provides: foo in their metadata

Full Example

h, err := dyalpm.NewHandle(rootDir, cacheDir, dyalpm.ArchLinux)
if err != nil {
    // handle error
}

syncDBs, err := h.SyncDBS()
if err != nil {
    // handle error
}

// Search for "foo" package (may be provided by another package)
targetName := "foo"
provider := h.FindDBSatisfier(syncDBs, targetName)

if provider != nil {
    fmt.Printf("%s is provided by: %s\n", targetName, provider.Name())
    fmt.Printf("Version: %s\n", provider.Version())
} else {
    fmt.Printf("No package found providing: %s\n", targetName)
}

Related Functions

• FindSatisfier(pkgs []Package, depstring) - Same concept but for an in-memory package list
• PackageIterator.FindSatisfier(depstring) - Works on iterator results from db.Search()
• pkg.Provides() []Depend - Get what a package provides (see package.go:144)