if

Begin a conditional statement. The simple format is:

if (expr
) cmd

There are three other possible formats, shown side-by-side:

if (expr
) then   if (expr
) then   if (expr
) then
   cmds
             cmds1
             cmds1

endif            else              else if (expr
) then
                    cmds2
             cmds2

                 endif             else
                                      cmds3

                                   endif

In the simplest form, execute cmd if expr is true; otherwise, do nothing (redirection still occurs; this is a bug). In the other forms, execute one or more commands. If expr is true, continue with the commands after then ; if expr is false, branch to the commands after else (or after the else if and continue checking). For more examples, see the earlier section "Expressions," or shift or while .

Example

Take a default action if no command-line arguments are given:

if ($#argv == 0) then
   echo "No filename given.  Sending to Report."
   set outfile = Report
else
   set outfile = $argv[1]
endif