Shell脚本无法使用grepped值设置环境变量

Question

In the shell script, I want to grep a value from the log file and set as the value of one environment. In the log file, there is one line like this:

SOME_PATH=/some/specific/path

In my shell script, I grep the SOME_PATH keyword, and I got the above line and split it with = , but I'm now able to set the environment variable:

line=`grep "SOME_PATH" /path/to/the/log.log`
path=${line##*=} 
export SOME_PATH="$path"  #I cannot change the environment variable with this line.

And if I just have the script like below, the environment variable changes.

export SOME_PATH=/some/specific/path

Answer 1

Exported variables available either in processes spawned from shell (script) which export ed a var or in another script with source d script with export statement.

1st way:

$ cat exp.sh
#!/bin/bash

export MYVAR="hi there"
bash
# or bash -c "echo here: $MYVAR"

2nd way:

$ cat exp.sh
#!/bin/bash

export MYVAR="hi there"

$ cat imp.sh
#!/bin/bash

. exp.sh

echo $MYVAR

Here's another explanation: advanced bash scripting guide .