This fetcher submodule fetches code from the Perforce source control system. The executable used is specified by FETCHCMD_p4, which defaults to "p4". The fetcher's temporary working directory is set by P4DIR, which defaults to "DL_DIR/p4".
[2] Yocto Project Reference Manual () <http://www.yoctoproject.org/docs/2.4/ref-manual/ref-manual.html#var-SRC_URI>