Re: File Handle questions

Declaring LOG_FH should, I think, fix both your posted problems.

You'll then find another problem with your $log_fh assignment. You need to assign a globref:

#my $log_fh = *LOG_FH;
my $log_fh = \*LOG_FH;
[download]

To be honest, I don't know why you're even bothering with that globally-scoped package variable. Why not just:

my $log_fh;
LOG_MSG_OPEN($log_fh,$logfile);
[download]

Recomendations:

Names with all uppercase characters are typically reserved for constants, filehandles, and so on. Using them for other purposes (e.g. LOG_MSG_OPEN in your post) can be confusing and error-prone.
Use the 3-argument form of open.
Consider using the autodie pragma.

Update: Expanded the "Names with all uppercase characters ..." point.

— Ken

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Re^2: File Handle questions by demichi (Beadle) on Oct 23, 2016 at 15:30 UTC
Hi, this `my $log_fh = \LOG_FH;` [download] does not help as I get the same errors. But returning the FH in the sub works :) `my $log_fh; # = \LOG_FH; $log_fh = LOG_MSG_OPEN($log_fh,$logfile); LOG_MSG($log_fh,$vbse,"v",$lglvl,5,"GENERAL","Starting Script $0"); ... module ... sub LOG_MSG_OPEN { my $par_fh = $_[0]; my $par_filepath = $_[1]; open($par_fh,"> $par_filepath") or die ("Can't open $par_filepath: + $!\n"); $par_fh->autoflush(1); return *$par_fh; } sub LOG_MSG { my $par_fh = shift (@_); ... print $par_fh "$logdate,$logtime,$SEV_KEYWORD,$par_FUNCTION,@line\ +n"; }` [download] Thanks for your other recommendations. I always used uppercase fos my subs. I will check the open and autodie. Kind regards, de Michi	[reply] [d/l] [select]
Re^3: File Handle questions by kcott (Archbishop) on Oct 27, 2016 at 13:20 UTC
"... `my $log_fh = \LOG_FH;` does not help as I get the same errors."* I suggested declaring `LOG_FH` to "fix both your posted problems". Using the globref, `\*LOG_FH`, was to handle an anticipated, subsequent problem. — Ken	[reply] [d/l] [select]
Re^2: File Handle questions by demichi (Beadle) on Oct 23, 2016 at 16:25 UTC
It looks like autodie is a very good idea. Can you give me an example how I can use my function (for logging) with autodie as I do it with die? With die: `unlink $filename or die LOG_MSG($par_lglvl,3,"DOUPGRADE","Could not de +lete $filename: $!");` [download] Thanks.	[reply] [d/l]
Re^3: File Handle questions by hippo (Archbishop) on Oct 23, 2016 at 22:27 UTC
`$ cat ad.pl #!/usr/bin/env perl use strict; use warnings; use autodie; unlink ('filewhichdoesnotexist'); print "Everything went fine.\n"; $ ./ad.pl Can't unlink('filewhichdoesnotexist'): No such file or directory at ./ +ad.pl line 6 $` [download] So you can simply redirect STDERR to the logfile of your choosing.	[reply] [d/l]
Re^3: File Handle questions by RonW (Parson) on Oct 25, 2016 at 22:45 UTC
Looking at autodie, it seems to not be easy to use with logging - other than redirecting STDERR in to your log file. Also, it doesn't seem to have a hook for providing a function for custom formatting. You could try using an `END` block to log the error after something `die`s. You could set up a $SIG{__DIE_} handler (see %SIG) to intercept the error and call your log function. HOWEVER, $SIG{__DIE_} handlers are called even when `die` is called inside an `eval`, so can be messy to get working correctly. Maybe overriding `CORE::GLOBAL::die()` would work for your purpose. You could follow the examples in autodie to "trap" the `die` with `eval`, then examine `$@` to determine whether and what to log. In your case, I'd say either redirect STDERR to your log file, or use `die LOG_MSG(...);` the way you are, now.	[reply] [d/l] [select]