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     prompt            The string an interactive C shell  prompts
                       with.   Noninteractive  shells  leave  the
                       prompt variable unset.  Aliases and  other
                       commands  in the .cshrc file that are only
                       useful interactively, can be placed  after
                       the  following  test:  `if ($?prompt == 0)
                       exit', to reduce startup time  for  nonin-
                       teractive  shells.   A  !   in  the prompt
                       string is replaced by  the  current  event
                       number.   The  default prompt is hostname%
-                       number.   The  default prompt is hostname%
                       for mere mortals,  or  hostname#  for  the
                       privileged user.

                       The setting of $prompt has three meanings:

                       $prompt  not  set     --   non-interactive
                       shell, test $?prompt.

                       $prompt set but == ""   --  .cshrc  called
                       by the which(1) command.

                       $prompt set and != "" --  normal  interac-
                       tive shell.