The simplest solution would have been to use sytem("wvdial &"). If I do this, however, I don't have a pid to kill when I'm done, at least not with a perl ipc solution. (I know that I could use ps to get wvdial's pid...)

My attempts with fork and open haven't been much more fruitful, but for different reasons. With fork, when I kill the child process, wvdial survives for some reason. And with

$pid = open WV
"-|""wvdial"<code>, <code>$pid
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is the pid of the fork, and not that of wvdial itself. So, once again, killing of the fork process isn't enough.

Here is my best try so far, using fork:

#!/usr/local/bin/perl
use strict;
use warnings;


++$|;

 print "Starting dial program\n";

 my $child;
  if ( $child = fork ) {
      print "Parent:\t$$\n";

      sleep 20; # wait for wvdial to do login
      while ( 1 ) {
      sleep 1;
      last if netcheck(); # check if network is up
      }
      if (( proc_check($child) ) && ( netcheck())) {
      print "Do stuff\n";
      system("fetchmail");
      system("wget", "http://www.example.com");
      }
      else {
      print  "Something's wrong: q to get out of here";
      }
      my $in = <>; # this is just a temporary end to the script for te
+sting
      if ( $in eq 'q' ) {
      kill -2, $child;
      exit;
      }
  }
  else { ### CHILD
      print "Child\t$$\n";
      system( "wvdial" );
  }

sub netcheck {
    my $net = `netstat -r`;
     if ( $net =~ m!ppp! ) {
    return 1;
    }
    else { 
    return 0;
    }
} # end netcheck

sub proc_check {
    my $pid = shift;
    unless ( kill 0 => $pid ) {
    print "Process $pid died or something\n";
    return 0;
    }
    return 1;
} # end proc_check
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