You can specify a number of discrete values—such as str1, str2, and so
on—for each condition, or you can specify a value with a wildcard. The last
condition should be the default and is executed if none of the other conditions
are met. For each of the specified conditions, all the associated statements
until breaksw are executed.
You can write the example that echoes the month when a number is given,
shown earlier for pdksh and bash, in tcsh as follows:
Click here to view code image
#!/bin/tcsh
set month = 5
switch ( $month )
case 1: echo "Month is January" ; breaksw
case 2: echo "Month is February" ; breaksw
case 3: echo "Month is March" ; breaksw
case 4: echo "Month is April" ; breaksw
case 5: echo "Month is May" ; breaksw
case 6: echo "Month is June" ; breaksw
case 7: echo "Month is July" ; breaksw
case 8: echo "Month is August" ; breaksw
case 9: echo "Month is September" ; breaksw
case 10: echo "Month is October" ; breaksw
case 11: echo "Month is November" ; breaksw
case 12: echo "Month is December" ; breaksw
default: echo "Oops! Month is Octember!" ; breaksw
endswYou need to end the statements under each condition with breaksw. If you
do not, the statements under the next condition are also executed.
The break and exit Statements
You should be aware of two other statements: the break statement and the
exit statement.
You can use the break statement to terminate an iteration loop, such as a
for, until, or repeat command.
You can use exit statement to exit a shell program. You can optionally use a
number after exit. If the current shell program has been called by another
shell program, the calling program can check for the code (the $? or
$status variable, depending on shell) and make a decision accordingly.