The for Statement
You use the for statement to execute a set of commands once each time a
specified condition is true. The for statement has a number of formats. The
first format used by pdksh and bash is as follows:
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for curvar in list
do
statements
done
You should use this format if you want to execute statements once for
each value in list. For each iteration, the current value of the list is assigned
to vcurvar. list can be a variable containing a number of items or a list
of values separated by spaces. The second format is as follows:
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for curvar
do
statements
done
In this format, the statements are executed once for each of the positional
parameters passed to the shell program. For each iteration, the current value
of the positional parameter is assigned to the variable curvar. You can also
write this format as follows:
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for curvar in $
do
statements
done
Remember that $@ gives you a list of positional parameters passed to the shell
program, quoted in a manner consistent with the way the user originally
invoked the command.
Under tcsh, the for statement is called foreach, and the format is as
follows:
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foreach curvar (list)
statements
end
In this format, statements are executed once for each value in list, and,