shell中的单引号和双引号

1. http://edsionte.com/techblog/archives/3712 echo和backslash

群记录：

2 这个只是变量，双引号的话会阻止shell的分词 echo "a    b"和echo a    b不一样
3 --------
4  "a    b"是echo的一个参数，而 echo a b 是echo的两个参数？
5
6
7 那echo -e  "\tz"   ，被shell解释成了什么呢？还是 “\tz” 吧？然后把"\tz"传给echo?
8 ---------
9 我这样理解对么~？
10 我为SUN狂.cc<walkerxk@gmail.com>  11:51:31
11 "\tz"被shell解释成了\tz，然后echo拿到的是\tz
12 11:45:03#tp#~> echo '"\tz"'
13 "\tz"
14 11:51:42#tp#~>
15 这里echo拿到的才是"\tz"

2. $@ $*区别 (man special paraments)

http://blog.sina.com.cn/s/blog_62c5db6e0100hpp8.html

http://m.oschina.net/blog/35905

参考代码：

2 #!/usr/bin/env bash
3 echo $#
4 echo "******"
5 for i in $*; do echo $i;  done
6 echo "--------"
7 for i in $@; do echo $i;  done
8 echo "--------"
9 for i in "$*"; do echo $i;  done
10 echo "--------"
11 for i in "$@"; do echo $i;  done
12 echo "@@@@@@@@"
13 for i in  "a" "bc"; do echo $i; done
14 exit
15
16 echo $*
17 echo $@
18 echo "$*"
19 echo "$@"
20
21
22
23 until [ -z "$*" ];
24 do
25  echo "$@"
26  shift
27 done

3. 关于test

http://17610376.blog.51cto.com/366886/405691

http://blog.csdn.net/ottocho/article/details/7248041

http://my.oschina.net/aiguozhe/blog/35937 test [ [[的区别

http://www.ibm.com/developerworks/cn/linux/l-bash-test.html ibm: bash测试和比较函数

http://hi.baidu.com/richardma_/blog/item/1e3672d6a87d5f0aa18bb7d1.html

4. eval shift

http://www.uplinux.com/shizi/wenxian/3778.html

http://hi.baidu.com/shenqb/blog/item/613835dd53d6d6d38d1029d9.html/cmtid/367ab064975ffbfff73654d3

5. 单引号双引号

http://hi.baidu.com/all_around_all/blog/item/13ef6431993f84db9d3d6264.html
http://www.51testing.com/?uid-47329-action-viewspace-itemid-86711

http://hi.baidu.com/outsmile/blog/item/4f0102c4b5bcbcc139db4985.html