本文主要將在shell中如何編寫for循環(huán)，并將循環(huán)變量作為下個(gè)shell腳本的參數(shù)。
shell for 循環(huán)：
#!第一種寫法 類似C、Java
for ((i=1; i=100; i ++))
do
echo $i
done
#!第二種寫法 in應(yīng)用
for i in {1..100}
do
echo $i
done
#!第三種寫法 seq 使用
for i in `seq 1 100`
do
echo $i
done
將循環(huán)變量賦值到下一個(gè)腳本：
在運(yùn)行shell腳本時(shí)候，有三種方式來調(diào)用外部的腳本，exec（exec script.sh）、source（source script.sh）、fork（./script.sh）
1、exec（exec /home/script.sh）：
使用exec來調(diào)用腳本，被執(zhí)行的腳本會(huì)繼承當(dāng)前shell的環(huán)境變量。但事實(shí)上exec產(chǎn)生了新的進(jìn)程，他會(huì)把主shell的進(jìn)程資源占用并替換腳本內(nèi)容，繼承了原主shell的PID號(hào)，即原主shell剩下的內(nèi)容不會(huì)執(zhí)行。
2、source（source /home/script.sh）
使用source或者“.”來調(diào)用外部腳本，不會(huì)產(chǎn)生新的進(jìn)程，繼承當(dāng)前shell環(huán)境變量，而且被調(diào)用的腳本運(yùn)行結(jié)束后，它擁有的環(huán)境變量和聲明變量會(huì)被當(dāng)前shell保留，類似將調(diào)用腳本的內(nèi)容復(fù)制過來直接執(zhí)行。執(zhí)行完畢后原主shell繼續(xù)運(yùn)行。
3、fork（/home/script.sh）
直接運(yùn)行腳本，會(huì)以當(dāng)前shell為父進(jìn)程，產(chǎn)生新的進(jìn)程，并且繼承主腳本的環(huán)境變量和聲明變量。執(zhí)行完畢后，主腳本不會(huì)保留其環(huán)境變量和聲明變量。
#!main.sh主體
#!/bin/sh
a=main
echo "a is $a"
echo "PID for parent before 2.sh:$$"
case $1 in
exec)
echo "using exec"
exec ./2.sh ;;
*)
echo "using sourcing"
source ./2.sh ;;
esac
echo "PID FOR parent after 2.sh :$$"
echo "now m"
#！2.sh
#!/bin/sh
echo "PID FOR 2.SH:$$"
echo "2.sh get a from main.sh is $a"
a=2.sh
export a
b=3.sh
echo "now 2.sh a is $a"
執(zhí)行結(jié)果：
a is main
PID for parent before 2.sh:1162
using sourcing
PID FOR 2.SH:1162
2.sh get a from main.sh is main`這里寫代碼片`
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1162
now m
通過for循環(huán)，循環(huán)變量作為2.sh變量賦值并執(zhí)行。
#！main主函數(shù)
#!/bin/sh
a=0
for ((i=1; i=10; i ++))
do
a=$i
echo "a is $a"
echo "PID for parent before 2.sh:$$"
echo "using sourcing"
source ./2.sh
echo "PID FOR parent after 2.sh :$$"
echo "now a is $a"
done
輸出結(jié)果：
a is 1
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 1
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
a is 2
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 2
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
a is 3
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 3
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
a is 4
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 4
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
a is 5
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 5
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
a is 6
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 6
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
a is 7
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 7
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
a is 8
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 8
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
a is 9
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 9
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
a is 10
PID for parent before 2.sh:1339
using sourcing
PID FOR 2.SH:1339
2.sh get a from main.sh is 10
now 2.sh a is 2.sh
PID FOR parent after 2.sh :1339
now a is 2.sh
以上這篇shell for循環(huán)、循環(huán)變量值付給其他shell腳本的方法就是小編分享給大家的全部?jī)?nèi)容了，希望能給大家一個(gè)參考，也希望大家多多支持腳本之家。
您可能感興趣的文章:- 詳解shell 變量的高級(jí)用法示例
- 處理Shell腳本中帶有空格的變量(bash腳本)
- shell判斷一個(gè)變量是否為空方法總結(jié)
- linux中shell的變量的數(shù)值計(jì)算
- Shell編程之特殊變量和擴(kuò)展變量詳解
- Shell編程之變量數(shù)值計(jì)算方法示例
- 詳解Shell編程之變量數(shù)值計(jì)算（二）
- 詳解Shell編程之變量數(shù)值計(jì)算（一）
- 淺談linux中shell變量$#,$@,$0,$1,$2的含義解釋
- 判斷Linux Shell環(huán)境變量是否存在
- Linux bash Shell中的變量類型詳解
- Linux Shell腳本系列教程（四）：使用函數(shù)添加環(huán)境變量
- Linux Shell腳本系列教程（三）：變量和環(huán)境變量
- 詳解shell 變量
