How to control execution of programs in a shell script.

Chrisantha1 · 04-27-2010, 12:22 AM

Dear LinuxQuestions,

Do you know how to write a shell script that executes say 4 instances of the same program in different directories at the same time, and once ONE instance completes it executes a new instance of that program in a new directory, and so on, until 100 instances have been executed, each in their own directory.

Cheers,
Chrisantha

grail · 04-27-2010, 12:49 AM

Maybe if you gave us an example we may be able to assist?

Chrisantha1 · 04-27-2010, 01:07 AM

I'm basically wanting to run several versions of a C++ genetic algorithm in Mac OS X. I want to run a batch of these programs on a server that has 5 nodes, and I want to start a new program each time one of the previous programs ends.

It seems this must consist of 3 parts.

1. Regular checking to see if a program has ended
2. Starting a program conditional upon this.
3. Making sure it starts in its own directory.

Basically, I have not done any sophisticated shell programming before.

Cheers,
Chrisantha

ntubski · 04-27-2010, 10:15 AM

Quote:

Basically, I have not done any sophisticated shell programming before.

Sophisticated shell programming is a bad idea.

Code:

#!/bin/sh
seq --format 'dirname%g' 100 | xargs --max-args=1 --max-procs=4 ./gene.sh

gene.sh:

Code:

#!/bin/sh

DIR="$1"

mkdir "$DIR"
cd "$DIR" || exit 1

/path/to/your/program

bigearsbilly · 04-28-2010, 02:45 AM

Quote:

Originally Posted by ntubski

Sophisticated shell programming is a bad idea.

never a truer word spoken.
they can be horrendous.

Chrisantha1 · 04-28-2010, 03:29 AM

Thank you I shall examine this and learn.

Chrisantha