摘要：
1 $$：显示PID编号[tandesir@localhost shell]$ echo $80682 $?：退出状态[tandesir@localhost shell]$ echo $?0[tandesir@localhost shell]$ ls test.txtls: 无法访问 test.txt: 没有那个文件或目录[tandesir@localhost shell]$ echo $?2[tandesir@localhost ~]$ true[tandesir@localhost ~]$ echo $?0[tandesir@localhost ~]$ false[tandesir@loc 阅读全文
摘要：
运用select和case可以制作简单的交互式菜单。#! /bin/bashselect CHIOCE in show help exitdo case "$CHIOCE" in show) ls ;; help) echo "Help : This is a joke for test!" ;; exit) exit 0 ;; esacdone 阅读全文
摘要：
【方法1】运用for in语句(1) bash#! /bin/bash
sum=0;
for i in {1..100}
do ((sum = sum + i))
done echo $sum
(2) perl#! /usr/bin/perl
$sum=0;
for ($i = 0; $i <=100 ; $i+=1)
{ $sum +=$i;
}
print "$sum\n";
【方法2】运用while语句(1) bash#! /bin/bash
i=0;
sum=0;
while [ "$i" -lt 100 ]
do ((i = i + .. 阅读全文