Linux BASH - 如何获取 EOF 标签内的变量值？
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BASH - how can i get the variable value inside the EOF tags?
提问by
I have this following script but i need to get $i variable value working inside that each block starting with EOF and ending with EOF.
我有以下脚本，但我需要让 $i 变量值在每个块中工作，以 EOF 开头并以 EOF 结尾。
its not reading the variable value but putting $i
它不是读取变量值而是将 $i
/var/tmp/vpn.sh i have:
/var/tmp/vpn.sh 我有：
#!/bin/bash
amazonEth0="10.0.0.18"
amazonWan0="4.9.2.9"
vpnServer="4.8.8.6"
hosttoHost1="10.109.0.20/32"
hosttoHost2="10.109.0.21/32"
hosttoHost3="10.109.58.6/32"
hosttoHost4="10.109.59.3/32"
for i in 1 2 3 4
do
cat > /tmp/test$i.conf << \EOF
#Step 3
conn test"$i"
#auto=start
type=tunnel
authby=secret
pfs=no
aggrmode=no
ikelifetime=28800s
lifetime=3600s
ike=aes128-md5;modp1024!
phase2alg=aes128-md5;modp1024
forceencaps=yes
left=$amazonLan0
leftid=$amazonWan0
leftsourceip=$amazonWan0
right=$vpnServer
rightsubnet=$hosttoHost$i
EOF
done
### Run me
cat > /var/tmp/vpn.sh << \EOF
service ipsec restart
######## Apply for loop here, instead of many many lines ###########
# for i in 1 2 3 4
# do
# ipsec auto --add test$i
# done
ipsec auto --add test1
ipsec auto --add test2
ipsec auto --add test3
ipsec auto --add test4
######## Apply for loop here, instead of many many lines ###########
# for i in 1 2 3 4
# do
# ipsec auto --up test$i
# done
ipsec auto --up test1
ipsec auto --up test2
ipsec auto --up test3
ipsec auto --up test4
ipsec auto --status
ip xfrm policy
ip route show
######## Apply for loop here, instead of many many lines ###########
# for i in 1 2 3 4
# do
# ping -c 1 $hosttoHost$i
# done
ping -c 1 10.109.0.20;
ping -c 1 10.109.0.21;
ping -c 1 10.109.58.6;
ping -c 1 10.109.59.3;
EOF
chmod +x /var/tmp/vpn.sh
# Cake - eat now - optional
/var/tmp/vpn.sh > save output | mail -s ipsec date time &
采纳答案by Pikrass
Remove the backslash before EOF:
删除之前的反斜杠EOF：
#!/bin/bash
i=ok
# This prints "Bwah ok"
cat <<EOF
Bwah $i
EOF
# This prints "Bwah $i"
cat <<\EOF
Bwah $i
EOF
To get your last line display rightsubnet="10.109.0.20/32"(for i=1), you need something like this:
要显示最后一行rightsubnet="10.109.0.20/32"（对于 i=1），您需要这样的东西：
i=1
val1=beep
val2=bop
rightval="val$i"
cat <<EOF
This is a beep: ${!rightval}
EOF
That is, you compute the name of the variable you want, put that in another variable, and use the ${!var}syntax.
也就是说，您计算所需变量的名称，将其放入另一个变量中，然后使用${!var}语法。
But for that kind of thing you should rather use an array:
但是对于那种事情，您应该使用数组：
i=0
vals=(beep bop)
cat <<EOF
This is a beep: ${vals[$i]}
EOF
Note however that the indexes start at 0.
但请注意，索引从 0 开始。
