unix - use of ssh variable in the shell script -


i want use variables of ssh in shell script. suppose have variable value got inside ssh , want use variable outside ssh in shell itself, how can ?

ssh my_pc2 <<eof <.. operations ..> a=$(ls -lrt | wc -l) echo \$a eof echo $a

in above example first echo print 10 inside ssh prints 10 second echo $a prints nothing.

i refine last answer defining special syntax passing required settings back, e.g. "#set var=value"

we put commands (that want run within ssh session) in cmdfile file this:

a=`id` b=`pwd` echo "#set a='$a'" echo "#set b='$b'"

and main script this:

#!/bin/bash  # ssh, run remote commands, , filter passed ssh user@host <cmdfile | grep "^#set " | sed 's/#set //' >vars.$$  # source variable settings passed . vars.$$ rm -f vars.$$  # have variables set echo "a = $a" echo "b = $b"

if you're doing lots of variables, can add function cmdfile, simplify/encapsulate special syntax passing data back:

passvar() {   var=$1   val=$2   val=${val:-${!var}}   echo "#set ${var}='${val}'" }  a=`id` passvar b=`pwd` passvar b

you might need play quotes when values include whitespace.


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