Invoking the Shell

A shell command interpreter can be invoked as follows:

 csh [options] [arguments] tcsh [options] [arguments] 

csh and tcsh use syntax resembling C and execute commands from a terminal or a file. Options -n, -v, and -x are useful when debugging scripts.

Options

• -b
• Allow the remaining command-line options to be interpreted as options to a specified command, rather than as options to csh itself.
• -c
• Execute command specified following the argument.
• -d
• Load directory stack from ~/.cshdirs even if not a login shell. (tcsh)
• -e
• Exit if a command produces errors.
• -f
• Fast startup; start without executing cshrc or tcshrc.
• -i
• Invoke interactive shell (prompt for input).
• -l
• Login shell (must be the only option specified).
• -m
• Load ~/.tcshrc even if effective user is not the owner of the file. (tcsh)
• -n
• Parse commands, but do not execute.
• -s
• Read commands from the standard input.
• -t
• Exit after executing one command.
• -v
• Display commands before executing them; expand history substitutions, but not other substitutions (e.g., filename, variable, and command). Same as setting verbose.
• -V
• Same as -v, but also display cshrc.
• -x
• Display commands before executing them, but expand all substitutions. Same as setting echo.
• -X
• Same as -x, but also display cshrc.

Arguments

Arguments are assigned, in order, to the positional parameters $1, $2, and so on. If the first argument is an executable script, commands are read from it, and remaining arguments are assigned to $1, $2, and so forth.