However - we are on perl 5.8.0 (corporate stuff.)

I really think this'll be a perl 5.8.0 issue - do you?

We're probably not free to go to 5.8.8 right now, but I believe I understand the problem now and what to watch out for.

See my earlier reply to self with what I found with exec /bin/false to force use of run-time lib _exit.

Thanks so much for your help.

Abe

I just played around with this some more (I somehow had the feeling that you know what you're doing... ;)  and I can now reproduce the problem. Initially, I had rather short content in my dummy SQL_REPORT_ID sections. So, to simulate longer read times, I added a sleep 1 like this

      ...

      while (<$fh>) {
         last if (/END SQL_REPORT_ID/) ;

         $Sql .= "$_";
      }
      sleep 1;

      ...
[download]

and now I'm getting this (when doing print STDERR "Generated $ReportId: $Sql"; in the child):

Generated 1: foo 1
Generated 2: foo 2
Generated 3: foo 3
Generated 4: foo 4
Generated 2: foo 2
Generated 3: foo 3
Generated 4: foo 4
(2..4 repeated ad infinitum...)
[download]

This is on HP-UX (no difference between 11.00, 11.11 and 11.23) — on Linux, however, everything is fine. I'll try other platforms later and report back...

For the record, my test file contains:

SQL_REPORT_ID 1
foo 1
END SQL_REPORT_ID

SQL_REPORT_ID 2
foo 2
END SQL_REPORT_ID

SQL_REPORT_ID 3
foo 3
END SQL_REPORT_ID

SQL_REPORT_ID 4
foo 4
END SQL_REPORT_ID
[download]

Update: in case anyone is interested, here are the results for a couple of other platforms I could find:

No problem on

• Linux (various versions, going back to kernel 2.2)
• AIX 4.3, 5.1, 5.3
• Mac OSX 10.4.10

but same problem as on HP-UX, on

• Solaris 2.6 (SunOS 5.6), Solaris 8, 9 and 10
• IRIX 6.5

(don't know what to make of it, yet...)

Aha - so it's not the perl version but it's probably perl on HPUX.

I'm not into this enough to look at perl source code, but I find it hard to imagine it's got something special about the way it calls close() for HPUX.

H'm. To me it means I have to be careful with explicitly opened files when calling fork(). perl open() is probably safe.

If you find out more do let me know, but I'm willing to use fork() now, just I know what to expect.

Thanks - Abe