Command Reference Guide

ch
216 Platform LSF Command Reference
ch
changes the host on which subsequent commands are to be executed
Synopsis
ch [-S] [-t] [host_name]
ch [-h | -V]
Description
Changes the host on which subsequent commands are to be executed.
By default, if no arguments are specified, changes the current host to the home host,
the host from which the
ch command was issued.
By default, executes commands on the home host.
By default, shell mode support is not enabled.
By default, does not display execution time of tasks.
The
ch command allows you to quickly change to a designated host with the same
execution environment. A simple shell is started that delivers all subsequent
commands (except built-in commands) to the designated host for execution.
When the simple shell starts, it is in the current working directory and has the same
command execution environment as that of the parent shell. Every remotely
dispatched command is executed with the same environment as that on the home
host. The syntax of the
ch command is similar to that of the Bourne shell. However,
there are some important differences.
The ampersand (
&) following a command line (representing a background job in
the Bourne shell) is ignored by
ch. You can submit background jobs in ch with the
built-in
post command and bring them into the foreground with the built-in
contact command (see below for details).
ch recognizes a ~ (tilde) as a special path name. If a ~ (tilde) is followed by a space,
tab, new line or / (slash) character, then the ~ character is translated into the user’s
home directory. Otherwise, the ~ is translated as the home directory of the user
name given by the string following the ~ character. Pipelines, lists of commands and
redirection of standard input/output are all handled by invoking
/bin/sh.
The following sequence of commands illustrates the behavior of the
ch command.
For example, the user is currently on
hostA:
ch hostB
hostB> ch hostC
hostC> ch
hostA> ... ...
Options
-S Starts remote tasks with shell mode support. Shell mode support is required for
running interactive shells or applications which redefine the
CTRL-C and CTRL-Z
keys (for example,
jove).