Transitive dependency

A transitive dependency is a functional dependency which holds by virtue of transitivity among various software components. A transitive dependency is a functional dependency which holds by virtue of transitivity among various software components. In a computer program a direct dependency is a functionality exported by a library, or API, or any software component that is referenced directly by the program itself. A transitive dependency is any dependency that is induced by the components that the program references directly.E.g. a call to a ''`UNIQ--templatestyles-00000001-QINU`''log() function will usually induce a transitive dependency to a library that manages the I/O to write the log message in a file. Dependencies and transitive dependencies can be resolved at different times, depending on how the computer program is assembled and/or executed: e.g. a compiler can have a link phase where the dependencies are resolved. Sometimes the build system even allows management of the transitive dependencies. Similarly, when a computer uses services, a computer program can depend on a service that should be started before to execute the program. A transitive dependency in such case is any other service that the service we depend directly on depends on, e.g. a web browser depends on a Domain Name Resolution service to convert a web URL in an IP address; the DNS will depend on a networking service to access a remote name server.The Linux boot system systemd is based on a set of configurations that declare the dependencies of the modules to be started: at boot time systemd analyzes all the transitive dependencies to decide the execution order of each module to start.