#!/bin/csh -vx #csh -vx show the command before running to help debug #just to check syntax #csh -n $0 #argv if ($#argv < 2) then     echo "Sorry, but you entered too few parameters"     echo "usage:  $0 arg1 arg2     exit endif set arg1 = $1 set arg2 = #2 foreach i ($*)    echo $i end    #execute commands echo "Hello there `whoami`.  How are you today?" echo "You are currently using `hostname` and the time is `date`" echo "Your directory is `pwd`" whoami hostname date pwd #var set name = Mark echo $name set name = "Mark Meyer" # if the string has space, must use "" echo $name # it means set to NULL set name = unset name # get user input set x = $<  set current_user = `whoami` #buildin vars echo $user      # who am I? echo $status    # a numeric variable, usually used to retun error codes #Arithmetic variables @ i = 2 @ k = ($x - 2) * 4 @ k = $k + 1 @ i-- @ i++ #array set name = (mark sally kathy tony) echo $#name    # num of the array echo $name[1] echo $name[4] echo $name[2-3] echo $name[2-]        # all elements from 2 to the end echo $name[1-3] echo $name[$i] set name = ($name doran) set name = (doran $name) set name = ($name[1-2] alfie $name[3-]) shift name  # get rid of the frist element of the array shift #if no argument is given, it will get rid of argv #Expressions and operators ==        equal     (either strings or numbers) !=        not equal     (either strings or numbers) =~        string match !~        string mismatch <=        numerical less than or equal to >=        numerical greater than or equal to >         numerical greater than <         numerical less than -e file           file merely exists (may be protected from user) -r file           file exists and is readable by user -w file           file is writable by user -x file           file is executable by user -o file           file is owned by user -z file           file has size 0 -f file           file is an ordinary file -d file           file is a directory !   -- negate                 &&  -- logical and ||  -- logical or #if-else # run cmd as if expression if ({grep -s junk $1}) then     echo "We found junk in file $1" endif # check if the var is defined if ($?dirname) then     ls $dirname endif if (-e somefile) then  grep $1 somefile else  echo "Grievous error!  Database file does not exist". endif #foreach foreach i (*)     if (-f $i) then         echo "============= $i ==================="         head $i     endif     if (-d $i) then         (cd $i; headers)     endif end #while while ($#argv > 0)     grep $something $argv[1] end @ n = 5 while ($n)      # do something      @ n-- end #switch-case switch ($argv[$i])  case quit:         break        # leave the switch statement  case list:         ls         breaksw  case delete:  case erase:         @ k = $i + 1         rm $argv[$k]         breaksw endsw     #here document grep $i <<HERE John Doe   101 Surrey Lane    London, UK    5E7 J2K Angela Langsbury   99 Knightsbridge, Apt. K4     Liverpool John Major  10 Downing Street  London HERE cat > tempdata <<ENDOFDATA 53.3 94.3 67.1 48.3 01.3 99.9 42.1 48.6 92.8 ENDOFDATA exit 0