qtcsh Usage

The invocation of qtcsh is exactly the same as for tcsh. qtcsh extends tcsh in providing support for the .qtask file and by offering a set of specialized shell built-in modes.

The .qtask file is defined as follows. Each line in the file has the following format:

% [!]app-name qrsh-options

The optional leading exclamation mark (!) defines the precedence between conflicting definitions in a global cluster .qtask file and the personal .qtask file of the qtcsh user. If the exclamation mark is missing in the global cluster file, a conflicting definition in the user file overrides the definition in the global cluster file. If the exclamation mark is in the global cluster file, the corresponding definition cannot be overridden.

app-name specifies the name of the application that, when typed on a command line in a qtcsh, is submitted to the grid engine system for remote execution.

qrsh-options specifies the options to the qrsh facility to use. These options define resource requirements for the application.

The application name must appear in the command line exactly as the application is defined in the .qtask file. If the application name is prefixed with a path name, a local binary is addressed. No remote execution is intended.

csh aliases are expanded before a comparison with the application names is performed. The applications intended for remote execution can also appear anywhere in a qtcsh command line, in particular before or after standard I/O redirections.

Hence, the following examples are valid and meaningful syntax:

# .qtask file
netscape -v DISPLAY=myhost:0
grep -l h=filesurfer

Given this .qtask file, the following qtcsh command lines:

netscape
~/mybin/netscape
cat very_big_file | grep pattern | sort | uniq

implicitly result in:

qrsh -v DISPLAY=myhost:0 netscape
~/mybin/netscape
cat very_big_file | qrsh -l h=filesurfer grep pattern | sort | uniq

qtcsh can operate in different modes, influenced by switches that can be set on or off:

• Local or remote execution of commands. Remote is the default.

• Immediate or batch remote execution. Immediate is the default.

• Verbose or nonverbose output. Nonverbose is the default.

The setting of these modes can be changed using option arguments of qtcsh at start time or with the shell built-in command qrshmode at runtime. See the qtcsh(1) man page for more information.