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Try executing a program until success

Problem

We want to constantly launch a program until it returns successfully, but we'd rather not use a Bash script.

Solution

Scheme can help script your system. The following script keeps running a program until success:

try-forever.scm

#!/bin/sh
#|
exec mzscheme -C "$0" "$@"
|#

(require (lib "process.ss"))

(define (main args)
  (define me (car args))
  (define program (find-executable-path (cadr args) #f))
  (define program-args (cddr args))
  (let loop ()
    (unless (apply system* program program-args)
      (loop))))

Discussion

Sample usage:

./try-forever.scm /sbin/dhclient -e -d eth0

Comments about this recipe

Contributors

-- DanielSilva - 23 Sep 2004