TCL script
set ::env(foo) "bar"
bash script
echo ${env(foo)}
echo $foo
I am able to print the environment variable in the TCL script but for some reason I can't print the environment variable in my bash script. What am I doing wrong?
1 Answer
If your bash script contains something like this (let's call it showenv)
#! /bin/bash
echo $foo
and your tcl
#! /usr/bin/tclsh
set ::env(foo) bar
exec ./showenv >>& /dev/tty
then, showenv will show
bar
that is, the tcl script sets the environment for its children processes.
answered May 11, 2021 at 17:39
Diego Torres Milano
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1 Comment
Donal Fellows
Environment variables never automatically go the other way, from child to parent. Instead, one has to write something (to standard out or to a file) that the caller interprets as an instruction to set an environment variable
foois in the environment of your shell, it's simplyecho "$foo". On startup, the shell simply defines a regular shell variable for each name in the environment that forms a valid shell identifier.