Re: bad die behaviour?

Let's see;

$ perldoc -f die
[download]

die LIST

Outside an "eval", prints the value of LIST to "STDERR" and exits with the current value of $! (errno). If $! is 0, exits with the value of "($? >> 8)" (backtick `command` status). If "($? >> 8)" is 0, exits with 255. ... snip ...

Let's see how this works.

$ perl -e '$! = 10; die "blah\n"'
blah
$ echo $?
10
[download]

Seems to work as described in the doco.

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Re^2: bad die behaviour? by Anonymous Monk on Sep 10, 2007 at 12:04 UTC
I have chosen a bad example trying to simplify the problem, as I have not realised that defining a sub is not executing it. In real world I have a module with utility subs and one of them is FatalError $msg as: `sub FatalError { my $message = shift; my ($package, $filename, $line) = caller; Log "ERROR","$message ($filename linea $line)"; CloseLog; die "ERROR: $message ($filename linea $line)\n"; }` [download] then I use it in a script as in: `$conn = Net::SFTP::Foreign::Compat->new($ftp_host,(user => $ftp_user)) +; if ( $conn->error ) { my $errormsg=$!; FatalError "Error: $errormsg"; }` [download] Result is the error message appears in the log but the script finishes with 0 return code. I have tried to force the return code with $! but with no positive result. Thanks Xavi	[reply] [d/l] [select]
Re^3: bad die behaviour? by ikegami (Patriarch) on Sep 10, 2007 at 12:40 UTC
I don't know why you're getting zero — you should never get zero from `die` — but your code is broken since `Log` and `CloseLog` probably change `$!`.	[reply] [d/l] [select]
Re^4: bad die behaviour? by Anonymous Monk on Sep 10, 2007 at 13:13 UTC
I also don't know why it returns 0. I have tried to force `$! = 1;` [download] just before the die and the script ends with return code 0 to the shell. The functions Log and CloseLog are very simple. They write a formatted log line and close the log file. thanks Xavi	[reply] [d/l]
Re^5: bad die behaviour? by ikegami (Patriarch) on Sep 10, 2007 at 13:26 UTC
Re^6: bad die behaviour? by Anonymous Monk on Sep 10, 2007 at 13:38 UTC
Some notes below your chosen depth have not been shown here
Re^3: bad die behaviour? by bruceb3 (Pilgrim) on Sep 10, 2007 at 21:22 UTC
Why do think that the Net::SFTP::Foreign::Compat will set $! if there is a problem? Looking at the source code for that module, the only time that $! is used is when there is a problem opening or communicating to a local file or pipe. Also, the doco for Net::SFTP::Foreign::Compat says that it will call die if there is a 'low-level protocol error or unexpected error message' so you would need to wrap your use of the module up in a eval block to catch the exception. On to the FatalError sub. `bruce:1:~/tmp $ cat p.pl #!/usr/bin/perl use strict; use warnings; sub Log { } sub CloseLog { } sub FatalError { my ($message, $exit_status) = @_; my ($package, $filename, $line) = caller; Log "ERROR", "$message ($filename linea $line)"; CloseLog; $! = $exit_status; die "ERROR: $message ($filename linea $line)\n"; } FatalError "testing", 34; # <- 34 should be the value of $? bruce:1:~/tmp $ ./p.pl ERROR: testing (./p.pl linea 19) bruce:1:~/tmp $ echo $? 34 bruce:1:~/tmp $` [download] Try rearranging your code. Good luck. Cheers.	[reply] [d/l]