I played around with ChatGPT today and got it to generate me a Perl script that forks children and restarts any that failed. Here's my initial prompt:
Write a Perl program that forks 5 child processes. The main process
should handle SIGCHILD and restart any child processes that have exite
+d.
The child processes have a function called "doWork" that have a
"Your code here" comment.
There was a bit back-and-forth to fix some bugs and to get ChatGPT to "use English". On the plus side, ChatGPT used "use strict; use warnings;" right from the start AND used readable indenting as well(*). Here's what it came up with:
Edit: Copied an old version at first, this is now the latest version
use strict;
use warnings;
use English qw( -no_match_vars );
use POSIX qw( :sys_wait_h );
# Fork 5 child processes
my $num_processes = 5;
for (my $i = 0; $i < $num_processes; $i++) {
my $pid = fork();
if ($pid == 0) {
# Child process
doWork();
exit;
} elsif (!defined $pid) {
die "Failed to fork: $OS_ERROR";
}
}
# Handle SIGCHILD and restart any child processes that have exited
$SIG{CHLD} = sub {
while ((my $pid = waitpid(-1, WNOHANG())) > 0) {
my $exit_code = $CHILD_ERROR >> 8;
if ($exit_code == 0) {
print "Child process $pid exited successfully\n";
} else {
print "Child process $pid exited with code $exit_code, res
+tarting\n";
my $new_pid = fork();
if ($new_pid == 0) {
# Child process
doWork();
exit;
} elsif (!defined $new_pid) {
die "Failed to fork: $OS_ERROR";
}
}
}
};
# Main process waits for child processes to exit
while (1) {
sleep(1);
}
# Function for child processes to do work
sub doWork {
# Your code here
print "Child process $$ doing some work\n";
sleep(10);
}
It's not perfect. The program doesn't exit when all children have finished and i would probably have to prompt it to add that functionality. But overall, i'd say it looks like a reasonable base framework.
What do you think? Any other problems i didn't catch?
(*) Any chance we could use whatever OpenAI used to train ChatGPT to train our newbies here on how to format code?
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