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Currently all shell command docs are put in the doc/usage root. Let's group them into cmd/ sub-directory. Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
65 lines
988 B
ReStructuredText
65 lines
988 B
ReStructuredText
echo command
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============
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Synopsis
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--------
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::
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echo [-n] [args ...]
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Description
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-----------
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The echo command prints its arguments to the console separated by spaces.
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-n
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Do not print a line feed after the last argument.
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args
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Arguments to be printed. The arguments are evaluated before being passed to
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the command.
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Examples
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--------
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Strings are parsed before the arguments are passed to the echo command:
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::
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=> echo "a" 'b' c
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a b c
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=>
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Observe how variables included in strings are handled:
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::
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=> setenv var X; echo "a)" ${var} 'b)' '${var}' c) ${var}
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a) X b) ${var} c) X
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=>
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-n suppresses the line feed:
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::
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=> echo -n 1 2 3; echo a b c
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1 2 3a b c
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=> echo -n 1 2 3
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1 2 3=>
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A more complex example:
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::
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=> for i in a b c; do for j in 1 2 3; do echo -n "${i}${j}, "; done; echo; done;
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a1, a2, a3,
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b1, b2, b3,
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c1, c2, c3,
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=>
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Return value
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------------
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The return value $? is always set to 0 (true).
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