how to prevent perl script from terminating

kamrul has asked for the wisdom of the Perl Monks concerning the following question:

Hi, I am using a library(Net::APNS::Persistent) that uses Net::SSLeay library for establishing SSL connection with Apples APNS servers. Apple server closes session if a wrong token is supplied. But, my problem is the Net::SSLeay library is terminating my program when the connection is dropped by Apple server.

As per my debugging this issue is occurring from line number 1895 of SSLeay.pm

$wrote = write_partial($ssl, $written, $to_write, $$data_ref);

I tried to catch if any exception, term signal were sent but no luck. If there is a network issue or any sort of error I expect it should show an error message/ exception that can be handled. But it simply kills the program without saying anything. So, how can I prevent write_partial() function from terminating my program ?

Comment on how to prevent perl script from terminating Download Code

Replies are listed 'Best First'.
Re: how to prevent perl script from terminating by t_rex_joe (Sexton) on May 20, 2015 at 17:44 UTC
You can use "eval" around the code.. `while (1) { $wrote = undef; eval { $wrote = write_partial($ssl, $written, $to_write, $$data_ref) +; 1; } or do { print "WRITE PARTIAL FAILED L: \"" . __LINE__ . "\"\n"; sle +ep 3; next; } if(defined $wrote) { print "WROTE: \"$wrote\". LAST L: \"" . __LINE__ . "\"\n"; last; } else { print "DO NOT KNOW HOW I GOT HERE WROTE: \"$wrote\". LAST L: + \"" . __LINE__ . "\"\n"; } } #EO WHILE` [download] Joe	[reply] [d/l]
Re^2: how to prevent perl script from terminating by kamrul (Acolyte) on May 20, 2015 at 18:01 UTC
Hi thanks for your reply. Im going to try that. One small question. Can you please explain why you are using the loop around the code ? Thanks in advanced ..	[reply]
Re^3: how to prevent perl script from terminating by GotToBTru (Prior) on May 20, 2015 at 18:22 UTC
The loop will keep trying the write_partial until it succeeds. Dum Spiro Spero	[reply]
Re^3: how to prevent perl script from terminating by kamrul (Acolyte) on May 20, 2015 at 18:14 UTC
Just tried like the below : `eval{ $wrote = write_partial($ssl, $written, $to_write, $$data_ref); }; print "Write error $@" if $@;` [download] But no luck! the script is terminating showing no error. Is there anything else I can try ?	[reply] [d/l]
Re: how to prevent perl script from terminating by Anonymous Monk on May 20, 2015 at 18:47 UTC
You've ruled out signals then? Did you try catch or ignore as with `$SIG{PIPE} = 'IGNORE';` ?	[reply] [d/l]
Re^2: how to prevent perl script from terminating by kamrul (Acolyte) on May 20, 2015 at 19:31 UTC
Hi, I didnt try with: $SIG{'PIPE'} = 'IGNORE' before. Now I can prevent it from stopping and catch the exceptions aswell ... Thanks a lot!!!	[reply]
Re: how to prevent perl script from terminating by GotToBTru (Prior) on May 20, 2015 at 18:33 UTC
The problem is probably not that a particular line in NET::SSLeay fails, but rather that line is part of a method that assumes the connection is still intact. I think that is probably your job: test to make sure the connection is still active before attempting to execute this method in the NET::SSLeay package. Dum Spiro Spero	[reply]