I didn't write it, and I don't know Perl very well at all.

We know. Regardless you have come to the right place for help.

The purpose of a lockfile is to tell other processes (ie copies of a CGI) to bugger off and wait their turn.

Anyway here is a pure Perl replacement that is identical to the lockfile call (well it is not IDENTICAL) because this actually works as the system call to lockfile should.... 

my $got_lock;
use Fcntl;   # to get constants for O_CREAT | O_EXCL | O_RDWR
for ( 0 .. 5 ) {
    if ( sysopen(my $fh, "$base_dir/.lock", O_CREAT | O_EXCL | O_RDWR,
+ 0600) ) {
        $got_lock = 1;
        close $fh;
      last;
    }
    sleep 2;
}
diehtml("Lock error $!\n") unless $got_lock;

[download]

That should be a cut and paste replacement for this: 

system ("lockfile -2 -r 5 $base_dir/.lock")  == 0
        or diehtml("Lock error: ", $? >> 8, "\n");
        # TODO stop stderr of system

[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In reply to Re: Re: Re: Perl script crashing at lockfile ? by tachyon
in thread Perl script crashing at lockfile ? by peterr

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