Ubuntu Manpage: hostlist - handle hostlist expressions

Provided by: python3-hostlist_2.2.1-1_all

NAME

       hostlist - handle hostlist expressions

SYNOPSIS

       hostlist [OPTION]... [HOSTLIST]...

DESCRIPTION

       Perform a set operation (union, intersection, difference or symmetric difference) on the given hostlists.
       Output the result as a hostlist, a count of hostnames or an expanded list of hostnames.

       If  "-" is used instead of a hostlist argument, an arbitrary number of hostlists are read from stdin. The
       union of them is used as if it had been present on the command line as a single hostlist argument.

OPTIONS

-u, --union
Compute the union of the hostlists. A hostname is present in the output if it is included in at
least one of the hostlists. This is the default operation.

-i, --intersection
Compute the intersection of the hostlists. A hostname is present in the output if it is included
in all the hostlists.

-d, --difference
Compute the difference of the hostlists. A hostname is present in the output if it is included in
the first hostlist but not any of the following.

-x, --symmetric-difference
Compute the symmetric difference of the hostlists. A hostname is present in the output if it is
included in an odd number of the hostlists.

-o OFFSET, --offset=OFFSET
Filter the result to skip OFFSET hosts from the beginning. If OFFSET is not less than the number
of hosts in the result, the result will become empty. If OFFSET is negative, keep -OFFSET hosts
from the end of the result. The default is to skip nothing.

-l LIMIT, --limit=LIMIT
Filter the result to limit it to the first LIMIT hosts. If LIMIT is not less than the number of
hosts in the result, this option does nothing. This filter is applied after the --offset filter
(see above). The default is to have no limit.

-c, --collapse
Output the result as a hostlist expression. This is the default. See the --chop option for
splitting into multiple hostlists of a certain size.

-n, --count
Output the number of hostnames in the result.

-e, --expand
Output the result as an expanded list of hostnames.

-w Output the result as an expanded list of hostnames. This option is deprecated. Use -e or --expand
instead.

-q, --quiet
Output nothing. This option is useful together with --non-empty.

-0, --non-empty
Return success if the resulting hostlist is non-empty and failure if it is empty.

-s SEPARATOR, --separator=SEPARATOR
Use SEPARATOR as the separator between the hostnames in the expanded list (and between (chopped)
hostlists in collapsed mode). The default is a newline.

-p PREPEND, --prepend=PREPEND
Output PREPEND before each hostname in the expanded list (and before each hostlist in collapsed
mode). The default is to prepend nothing.

-a APPEND, --append=APPEND
Output APPEND after each hostname in the expanded list (and after each hostlist in collapsed
mode). The default is to append nothing.

-S FROM,TO, --substitute=FROM,TO
Apply a regular expression substitution to each hostname, replacing all FROM with TO. The default
is to do no substitution.

--append-slurm-tasks=SLURM_TASKS_PER_NODE
Append the number of tasks parsed from the SLURM_TASKS_PER_NODE string. You need to use
-e/--expand and you probably need to specify -a/--append and -s/--separator too. NOTE: The
hostlist is always sorted internally by this program. The task counts from SLURM_TASKS_PER_NODE is
then applied to each hostname in the sorted list.

--repeat-slurm-tasks=SLURM_TASKS_PER_NODE
Repeat each hostname so it is listed multiple times as specified by the SLURM_TASKS_PER_NODE
string. You need to use -e/--expand. NOTE: The hostlist is always sorted internally by this
program. The task counts from SLURM_TASKS_PER_NODE is then applied to each hostname in the sorted
list.

--chop=CHUNKSIZE
When outputting as collapsed hostlist (the default mode --collapse) split into hostlists of size
CHUNKSIZE and output each hostlist separately. The last hostlist may be smaller than the rest.

--version
Show the version of the utility and the underlying Python library.

EXAMPLES

       Output the union of n[10-19] and n[15-24] (which is n[10-24]):
              hostlist n[10-19] n[15-24]

       Output the result of removing n15 and n[17-18] from n[1-20] (which is n[1-14,16,19-20]):
              hostlist -d n[1-20] n15 n[17-18]

       Output the result as an expanded list of hostnames (one hostname per line):
              hostlist -d -e n[1-20] n15 n[17-18]

       Output the result as an expanded list of hostnames separated by commas:
              hostlist -d -e -s, n[1-20] n15 n[17-18]

       Output the result as an expanded list of hostnames (followed by space and the digit "8") separated by
       spaces:
              hostlist -d -e -s " " -a " 8" n[1-20] n15 n[17-18]

       Expand a hostlist, replacing "n" with "ni":
              hostlist -e -S n,ni n[1-20]

       Print INCLUDED as n11 is in n[10-20]:
              if hostlist -q0 -i n11 n[10-20]; then echo INCLUDED; else echo NOT INCLUDED; fi

AUTHOR

       Written by Kent Engström <kent@nsc.liu.se>.

       The program is published at http://www.nsc.liu.se/~kent/python-hostlist/

NOTES

       The square brackets used in the hostlist expression syntax are also used in shell glob patterns. This may
       cause  unwanted  surprises  if  you have files in your current directory named after hosts present in the
       hostlist. Always quote the hostlist expression to avoid this problem:

         % hostlist n[1-10]
         n[1-10]
         % touch n1
         % hostlist n[1-10]
         n1
         % echo n[1-10]
         n1
         % hostlist "n[1-10]"
         n[1-10]