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- for command
- ===========
- Synopis
- -------
- ::
- for <variable> in <items>; do <commands>; done
- Description
- -----------
- The for command is used to loop over a list of values and execute a series of
- commands for each of these.
- The counter variable of the loop is a shell variable. Please, keep in mind that
- an environment variable takes precedence over a shell variable of the same name.
- variable
- name of the counter variable
- items
- space separated item list
- commands
- commands to execute
- Example
- -------
- ::
- => setenv c
- => for c in 1 2 3; do echo item ${c}; done
- item 1
- item 2
- item 3
- => echo ${c}
- 3
- => setenv c x
- => for c in 1 2 3; do echo item ${c}; done
- item x
- item x
- item x
- =>
- The first line ensures that there is no environment variable *c*. Hence in the
- first loop the shell variable *c* is printed.
- After defining an environment variable of name *c* it takes precedence over the
- shell variable and the environment variable is printed.
- Return value
- ------------
- The return value $? after the done statement is the return value of the last
- statement executed in the loop.
- ::
- => for i in true false; do ${i}; done; echo $?
- 1
- => for i in false true; do ${i}; done; echo $?
- 0
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