Using groovy, how do you pipe multiple shell commands?

Question

Using Groovy and it\'s java.lang.Process support, how do I pipe multiple shell commands together?

Consider this bash command (and assume your username i

Answer 1

This works for me :

def p = 'ps aux'.execute() | 'grep foo'.execute() | ['awk', '{ print $1 }'].execute()
p.waitFor()
println p.text

for an unknown reason, the parameters of awk can't be send with only one string (i don't know why! maybe bash is quoting something differently). If you dump with your command the error stream, you'll see error relative to the compilation of the awk script.

Edit : In fact,

1. "-string-".execute() delegate to Runtime.getRuntime().exec(-string-)
2. It's bash job to handle arguments containing spaces with ' or ". Runtime.exec or the OS are not aware of the quotes
3. Executing "grep ' foo'".execute() execute the command grep, with ' as the first parameters, and foo' as the second one : it's not valid. the same for awk