NAME

       hwloc-patch - Apply a topology difference to an existing XML topology

SYNOPSIS

       hwloc-patch [options] [<topology.xml> | refname] [<diff.xml> | -] <output.xml>

       hwloc-patch [options] [<topology.xml> | refname] [<diff.xml> | -]

OPTIONS

       -R --reverse
                 Reverse the sense the difference file.

       --version Report version and exit.

DESCRIPTION

       hwloc-patch  loads  the  difference  between  two  topologies from a XML file (or from the
       standard input) and applies it to an existing topology, generating a new, modified one.

       The XML difference may have been computed earlier with hwloc-diff or hwloc-compress-dir.

       If <output.xml> is given,  the  new,  modified  topology  is  stored  in  that  new  file.
       Otherwise, <topology.xml> is modified in place.

       If   refname   is  given  instead  of  <topology.xml>,  the  input  topology  filename  is
       automatically guessed by reading the refname field of  the  XML  diff  file.   By  default
       hwloc-diff  generates  XML  diffs  with the right reference topology filename (without any
       path prefix).

       If - is given instead of <diff.xml>, the topology difference is  read  from  the  standard
       input.

       NOTE:  If  some  application-specific  userdata were been exported to the input XMLs, they
       will be ignored and discarded from the output because hwloc has no way to  understand  and
       patch them.

       NOTE:  It  is  highly  recommended that you read the hwloc(7) overview page before reading
       this man page.  Most of the concepts described in hwloc(7) directly apply  to  the  hwloc-
       patch utility.

EXAMPLES

       hwloc-patch's operation is best described through several examples.

       Apply a XML topology difference file to an existing topology:

           $ hwloc-patch fourmi023.xml diff.xml fourmi023-new.xml

       Apply  a  XML  topology  difference  file  whole  refname  field  contains the right input
       topology:

           $ hwloc-patch refname diff.xml fourmi023-new.xml

       Apply a XML topology from the standard intput:

           $ cat diff.xml | hwloc-patch fourmi023.xml - fourmi023-new.xml

       Directly compute the difference between two topologies and apply it  to  another  one,  in
       place:

           $ hwloc-diff fourmi023.xml fourmi024.xml | hwloc-patch fourmi025.xml -

RETURN VALUE

       Upon successful execution, hwloc-patch outputs the modified topology.  The return value is
       0.

       hwloc-patch also returns nonzero if any kind of error occurs, such as (but not limited to)
       failure to parse the command line.

SEE ALSO

       hwloc(7), lstopo(1), hwloc-diff(1), hwloc-compress-dir(1)