问题:

I have two scripts that are being run. One runs from a client workstation and calls a script on a server. I need a variable from the server script and I figured I could do it this way, but it isn't working:

#!/bin/sh

local_var=""

ssh user@server " $local_var=\$server_var "

echo "$local_var"

My output of local_var is null. Is there a way to do this?

回答1:

Try:

local_var=$(ssh user@server "echo ${server_var}")

回答2:

yes, you need to print the variable names and values, then source the output of that. An example:

$ source <(ssh user@server 'echo foo=\"$bar\"')
$ echo $foo
bar

This works on bash, it may not work on shells which does not support redirecting command output to source. For those shells, you may need to create a temporary file first.

回答3:

I'm going to make 3 assumptions:

The remote machine is a Linux box.
You know the process ID of the remote script's instance.
The variable you want is in the remote process's environment.

Assuming the above, the following should work:

local_var=$( ssh user@server bash -c '
   while IFS="=" read -d '' -r name value; do
     [[ $name = "server_var" ]] && echo $server_var && break
   done' < /proc/$REMOTE_SCRIPT_PROC_ID/environ )