在 Bash 脚本中随机选择并打印三个字符串之一
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Pick and print one of three strings at random in Bash script
提问by Switchkick
How can print a value, either 1, 2 or 3 (at random). My best guess failed:
如何打印值，1、2 或 3（随机）。我最好的猜测失败了：
#!/bin/bash
1 = "2 million"
2 = "1 million"
3 = "3 million"
print randomint(1,2,3)
回答by codaddict
To generate random numbers with bash use the $RANDOMinternal Bash function:
要使用 bash 生成随机数，请使用$RANDOM内部 Bash 函数：
arr[0]="2 million"
arr[1]="1 million"
arr[2]="3 million"
rand=$[ $RANDOM % 3 ]
echo ${arr[$rand]}
From bash manual for RANDOM:
来自 RANDOM 的 bash 手册：
Each time this parameter is referenced, a random integer between 0 and 32767 is generated. The sequence of random numbers may be initialized by assigning a value to RANDOM. If RANDOM is unset,it loses its special properties, even if it is subsequently reset.
每次引用此参数时，都会生成 0 到 32767 之间的随机整数。随机数序列可以通过给 RANDOM 赋值来初始化。如果 RANDOM 未设置，它就会失去它的特殊属性，即使它随后被重置。
回答by Lukasz Andersson
64 chars alpha numeric string
64 个字符的字母数字字符串
randomString32() {
index=0
str=""
for i in {a..z}; do arr[index]=$i; index=`expr ${index} + 1`; done
for i in {A..Z}; do arr[index]=$i; index=`expr ${index} + 1`; done
for i in {0..9}; do arr[index]=$i; index=`expr ${index} + 1`; done
for i in {1..64}; do str="$str${arr[$RANDOM%$index]}"; done
echo $str
}
回答by Marty McGowan
~.$ set -- "First Expression" Second "and Last"
~.$ eval echo $$(expr $RANDOM % 3 + 1)
and Last
~.$
