RE: Having trouble porting an application to MS-Windows

-----Original Message-----
From: Chas Owens [mailto:chas.owens@xxxxxxxxx]
Sent: Friday, June 15, 2007 10:55 AM
To: Bob McConnell
Cc: beginners@xxxxxxxx
Subject: Re: Having trouble porting an application to MS-Windows

On 6/15/07, Bob McConnell <rvm@xxxxxxxxx> wrote:
snip
eval {
local $SIG{ALRM} = sub { die
"alarm\n" }; # NB:
\n required
alarm $timeout;
$nread = sysread PORT, $line, 1;
alarm 0;
};
snip
This transmits the packet, but never comes out of the eval() if it
doesn't receive a character. Is there anything obvious that
I missed?
snip

Hmm, that codes looks right. Do the two scripts I sent earlier work?


Yes, both work with the output below. The difference is that both of
yours interrupt an empty while loop, but my code is in a sysread() call.
The SIGINT I use to kill the process can interrupt the system call, but
will the alarm? Or have I found a bug in the ActiveState implementation?

Bob McConnell

D:\Perl\eg\SIMscript>perl forka.pl
Fri Jun 15 11:16:36 2007
timeout
Fri Jun 15 11:16:39 2007

D:\Perl\eg\SIMscript>perl forkb.pl
parent Fri Jun 15 11:12:57 2007
parent waiting 10 seconds
child Fri Jun 15 11:12:57 2007
child waiting 1 seconds
timeout child
child Fri Jun 15 11:12:58 2007
timeout parent
parent Fri Jun 15 11:13:07 2007
.

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