qtcsh.1

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

       o  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);

       o  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);

       o  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

       o  tasks are executed remotely;

       o  immediate or batch execution is requested;

       o  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.

SEE ALSO

       sge_intro(1), qrsh(1), qtask(5) as well as tcsh(1).

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.



SGE 8.1.3pre                      2011-10-21                          QTCSH(1)