idioms for returning multiple values in shell scripting

Question

Are there any idioms for returning multiple values from a bash function within a script?

http://tldp.org/LDP/abs/html/assortedtips.html describes how to echo multiple values and process the results (e.g., example 35-17), but that gets tricky if some of the returned values are strings with spaces in.

A more structured way to return would be to assign to global variables, like

foo () {     FOO_RV1="bob"     FOO_RV2="bill" }  foo echo "foo returned ${FOO_RV1} and ${FOO_RV2}" 

I realize that if I need re-entrancy in a shell script I'm probably doing it wrong, but I still feel very uncomfortable throwing global variables around just to hold return values.

Is there a better way? I would prefer portability, but it's probably not a real limitation if I have to specify #!/bin/bash.

Answer 1

This question was posted 5 years ago, but I have some interesting answer to post. I have just started learning bash, and I also encounter to the same problem as you did. I think this trick might be helpful:

#!/bin/sh  foo="" bar=""  my_func(){     echo 'foo="a"; bar="b"' }  eval $(my_func) echo $foo $bar # result: a b 

This trick is also useful for solving a problem when a child process can not send back a value to its parent process.