Linux Shell中的\$#、\$@、\$0

文章作者:Tyan
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1. \$

在Linux Shell脚本中,$#用来表示传入的参数数量。例如:

  • shell脚本test0
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#!/bin/bash
# test $#

echo "The number of parametes is $#."
  • 执行结果
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$ ./test0
The number of parametes is 0.

$ ./test0 1 2 3
The number of parametes is 3.

$ ./test0 a bc
The number of parametes is 2.

2. \$@

在Linux Shell脚本中,$#用来表示传入的参数列表。例如:

  • shell脚本test1
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#!/bin/bash
# test $@

echo "The parametes are $@."
  • 执行结果
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$ ./test1
The parametes are .

$ ./test1 1 2 3
The parametes are 1 2 3.

$ ./test1 a bc
The parametes are a bc.
  • 遍历$@
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for var in $@
do
echo "$var"
done

3. \$0,\$1

在Linux Shell脚本中,$0用来表示要执行的shell脚本名称。$1$2用来表示传入到脚本中对应位置的参数,例如:

  • shell脚本test2
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#!/bin/bash
# test $0,$1

echo "The shell is $0."
echo "The first parameter is $1."
echo "The first parameter is $2."
  • 运行结果
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$ ./test2
The shell is ./test2.
The first parameter is .
The first parameter is .

$ ./test2 1 2
The shell is ./test2.
The first parameter is 1.
The first parameter is 2.

$ ./test2 a 2
The shell is ./test2.
The first parameter is a.
The first parameter is 2.

$ ./test2 a b
The shell is ./test2.
The first parameter is a.
The first parameter is b.

$ ./test2 a b c
The shell is ./test2.
The first parameter is a.
The first parameter is b.
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