# for 循环declare -i i s
for(( i=1; i<=100; i++))dolet s+=i
donefor i in{
1..5}doecho$idonefor a in{
a..z}doecho$adone
data="name,sex,rollno,location"
oldIFS=$IFS
IFS=","for item in$data;doecho$itemdone# while循环 until循环declare -i i=0 s=0
while((i<=100))dolet s+=i
let i++
doneuntil((i>200))dolet s+=i
set i++
done# while read 读取文件whileread line
doecho$linedone< a.txt
IFS=':'whileread f1 f2 f3 f4 f5
doecho$f1done<"etc/passwd"# untiluntil(( i >100))doecho$ilet i++
done# 循环控制# break continue
select
select f in *
doecho"$REPLY, you have chosen $f"breakdone
PS3="please chosen: "# 修改默认的提示符
oldIFS=$IFS
IFS=','
menu="C/C++,PHP,Golang,JAVA,Python,JavaScript"select choice in$menudoecho"You have chosen: $REPLAY, selection list $choice"breakdone
IFS=$oldFIS
function getline(){
local i=1 # 局部变量whileread line
dolet ++i
echo"$i line: $line"done<$file}
file="a.txt"
getline a.txt
function append(){
echo$1$2$3echo"$@"# 所有参数, 每个参数是独立echo"$*"# 所有参数, 参数是连续的}
append a b c d e f