Initial commit

2023-05-08 17:57:52 +00:00
commit 194457e662
8 changed files with 171 additions and 0 deletions
@@ -0,0 +1,50 @@
+#!/usr/bin/perl
+use strict;
+use File::Path qw/make_path/;
+
+my $pidpath = '/tmp/runonce_pid';
+
+if(!-d $pidpath) {
+        make_path($pidpath) || die "Unable to create $pidpath: $!\n";
+        chmod(0777, $pidpath) || die "Unable to chmod $pidpath: $!\n";
+}
+
+my $waitmode=0;
+if(lc($ARGV[0]) eq '-w') {
+        $waitmode=1;
+        shift(@ARGV);
+}
+
+my($tag,@cmd)=@ARGV;
+if(!$tag || !@cmd) {
+        die "Usage: $0 <tag> <cmd>\n";
+}
+
+my $file = "$pidpath/$tag";
+for(;;) {
+        if(-e $file) {
+                open(IN, $file) || die "Unable to read $file: $!\n";
+                my $pid=<IN>;
+                close(IN);
+                chomp($pid);
+
+                if(kill(0, $pid)) {
+                        print "$pid is alive\n";
+                        exit(0) unless($waitmode);
+                        sleep(1);
+                } else {
+                        last;
+                }
+        } else {
+                last;
+        }
+}
+
+open(OUT, ">", $file) || die "Unable to write $file: $!\n";
+print OUT $$;
+close(OUT);
+
+my $res=system(@cmd);
+
+unlink($file) || die "Unable to unlink $file: $!\n";
+exit($res);