Ubuntu Manpage: qtcsh - tcsh with transparent remote execution by use of qrsh

Provided by: gridengine-client_8.1.9+dfsg-7build1_amd64

NAME

       qtcsh - tcsh with transparent remote execution by use of qrsh

SYNTAX

       qtcsh [ tcsh options | -ABLR ]

DESCRIPTION

Qtcsh is an extension to the popular csh(1) derivative tcsh. It allows the transparent
remote execution of commands entered in qtcsh controlled via Grid Engine. Qtcsh can be
used as interactive command interpreter as well as for the processing of tcsh shell
scripts.

When invoked, qtcsh identifies which commands are to be run remotely and which are not.
For this purpose the files <sge_root>/<cell>/common/qtask and ~/.qtask are processed. Each
line in these files defines a command that is intended to be run remotely (see qtask(5)
for a definition of the file format). The .qtask file in the user's home directory
contains the user's remote task specification, while the file in the common directory is
maintained by the administrator and defines a cluster-wide default behavior. The contents
of the administrator supplied qtask(5) file are completely overridden in case there is an
appropriate entry in the users qtask(5) file. This is prevented in case an exclamation
mark is prefixed to the command name in the administrators qtask file.

Qtcsh always attempts to start the designated tasks remotely via qrsh(1). Exceptions are

• if the user enters such commands via a relative or absolute pathname instead of the
stand-alone command name (see qtask(5) for more information);

• if the environment variable JOB_ID is set and thus qtcsh assumes that execution already
happens remotely within a Grid Engine job and thus executes tasks locally. This avoids
unwanted recursions but can be overridden by the command-line option -R and the built-
in command qrshmode -R (see corresponding descriptions below);

• if qtcsh cannot establish a connection of Grid Engine during start-up. This allows
using qtcsh as a login shell without the danger of being blocked when no Grid Engine
service is available.

Qtcsh can operate in three different modes determining whether

• tasks are executed remotely;

• immediate or batch execution is requested;

• status output is verbose or only in case of any errors.

These modes either can be controlled by the command-line switches described below during
qtcsh invocation or within an executing qtcsh via the built-in command qrshmode, as
described in section BUILT-IN COMMANDS.

OPTIONS

       The options listed below are specific to qtcsh.  The  user  is  referred  to  the  tcsh(1)
       documentation for the explanation of further options.

       -A     Switches  qtcsh  into  verbose  mode,  causing  diagnostic output in case of remote
              execution.

       -B     Switches remote task execution into batch mode. Tasks submitted to Grid Engine will
              be  queued  if  they  cannot  start immediately.  As a consequence, qtcsh may block
              until the queued task can be started by Grid Engine. While this  behavior  probably
              is  undesirable  during an interactive session, it may be very useful for execution
              of shell scripts through qtcsh,  as  it  avoids  failure  of  the  scripts  due  to
              temporarily unavailable resources for particular tasks.

       -L     Switches  off  the  default  behavior  of  remote execution of commands. Causes all
              commands to be executed locally even if they are contained in one of  the  qtask(5)
              files.

       -R     Enforces  remote  execution  of  commands  even  if  JOB_ID  is  set as environment
              variable.

BUILT-IN COMMANDS

       This section only describes additional shell builtin commands which are not  available  in
       standard tcsh(1).

       qrshmode [-ANBILR]
              Without  options,  the  current operational mode of qtcsh is displayed. The options
              have the following effect:

              -A   switch to verbose output mode
              -N   switch to non-verbose output mode
              -B   switch to batch execution mode
              -I   switch to immediate execution mode
              -L   always execute commands locally
              -R   execute configured commands remotely

ENVIRONMENT VARIABLES

       SGE_ROOT       Specifies the location of the Grid Engine standard configuration files.

       SGE_CELL       If set, specifies the default Grid Engine cell. To address  a  Grid  Engine
                      cell qtcsh uses (in the order of precedence):

                             The name of the cell specified in the environment variable SGE_CELL,
                             if it is set.

                             The name of the default cell, i.e. default.

       SGE_DEBUG_LEVEL
                      If set, specifies that debug information should be written  to  stderr.  In
                      addition  the  level  of  detail in which debug information is generated is
                      defined.

       SGE_QMASTER_PORT
                      If set, specifies the tcp port  on  which  sge_qmaster(8)  is  expected  to
                      listen  for communication requests.  Most installations will use a services
                      map entry for the service "sge_qmaster" instead to define that port.

       JOB_ID         If set when starting qtcsh the local operation mode is activated implicitly
                      as if the -L option was specified.

FILES

       ~/.qtask       user qtask file.
       <sge_root>/<cell>/common/qtask
                      cluster qtask file.

COPYRIGHT

       Qtcsh  is  an  adaptation of tcsh which is copyrighted by The Regents of the University of
       California.

       See sge_intro(1) and the information provided in <sge_root>/doc/LICENCES for  a  statement
       of further rights and permissions.