How can a shell script control another script

I remember vaguely a technique using pipes f开发者_如何学Pythonor communication between two shell processes.

Are there any tutorials available on how to setup and control a subshell?

Are you talking about named pipes?

mkfifo pipe
ls -l >pipe #type this is one shell
cat <pipe #type this is another one

No one reads if no one writes.
No one writes if no one reads.

Did you take a look at the Advanced Bash Scripting guide?

There's an entire chapter about - surprise surprise - subshells.

This should get you going, examples are in C, but the same technique applies to bash. Just do a search for named pipes, in google or here, alot of examples specific to bash pops up.

http://developers.sun.com/solaris/articles/named_pipes.html

I think you want coprocesses. In bash 4 there is a new builtin "coproc".

See here for examples:

http://tldp.org/LDP/abs/html/bashver4.html