使用sed更改配置的Bash脚本

Question

I'm trying to change the value of malloc to say 1234m via a bash script but not seeing any changes. I presume it is an issue with my regex, can anybody see what I've done inncorrectly?

String

DAEMON_OPTS="-a :6081 \
             -T localhost:6082 \
             -f /etc/varnish/default.vcl \
             -S /etc/varnish/secret \
             -s malloc,256m"

Code

# get the memory allocation
echo "Enter the memory allocation"
read malloc

# update the default config
sed -ie 's/malloc,.*[0-9m]$/malloc,'$malloc'/gI' /etc/default/varnish

Answer 1

You are missing a " before the $ in the sed pattern.

By the way, your pattern works, but in a different way than you probably intended: the character class [0-9m] matches just one character, m in this case. The number is being matched by .* . Better pattern might be malloc,[0-9]\\+m"$ .

Answer 2

Try this sed command:

On Mac:

sed -E 's/malloc,[0-9]+m/malloc,'$malloc'/' /etc/default/varnish

or on Linux:

sed -r 's/malloc,[0-9]+m/malloc,'$malloc'/' /etc/default/varnish

Answer 3

以下sed行为我工作，将其括在"而不是' ：

 sed -ie "s/malloc,[0-9]\+m$/malloc,$malloc/gI" /etc/default/varnish