Perl Seems to be giving me random errors

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

I started using perl about a year ago. I am pretty sure the errors I get really aren't random but they seem that way. Most of the time it runs fine but 10% of the time I will get internal server error or unrecognized character at some completely irrelavent place in my code and it is at different places all the time. Example... Unrecognized char at.. blah near $ENV{'SCRImT_NAME'} and that is defiantly SCRIPT in code. If I hit refresh the page comes up fine. If I keep hitting refresh over and over it will happen again at a differnt spot. Seems to be randomly changing a character in code. I have no idea where to start looking to fix this. Does anyone know a common error that could cause this? My code is extremely long to post and I have no idea where in it this could be.

Comment on Perl Seems to be giving me random errors

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Re: Perl Seems to be giving me random errors by Crackers2 (Parson) on Nov 15, 2004 at 14:44 UTC
Sounds like bad memory to me. If it's your own server, i suggest running memtest86, otherwise notify your server admin and let him/her handle it. Then again, when looking at your specific example ( P being replaced with m ) the difference is more than just a single bit error, so i might very well be wrong.	[reply]
Re: Perl Seems to be giving me random errors by trammell (Priest) on Nov 15, 2004 at 14:40 UTC
One thing you can do is run your Perl CGI script from the command line; this decouples Perl from your web server and browser, and lets you establish whether or not Perl is really part of the problem here.	[reply]
Re: Perl Seems to be giving me random errors by Grygonos (Chaplain) on Nov 15, 2004 at 15:00 UTC
`use CGI::Carp qw{fatalsToBrowser}` would also help here.And `use strict; use warnings; use CGI;` [download] if you're not already. Grygonos	[reply] [d/l] [select]
Re^2: Perl Seems to be giving me random errors by waswas-fng (Curate) on Nov 15, 2004 at 15:49 UTC
And then after debugging remove the se CGI::Carp qw{fatalsToBrowser} so as not to give too much information to hackers when they are testing the cgi. It dumps way to much info about how the script is constructed when used on live apps. -Waswas	[reply]
Re: Perl Seems to be giving me random errors by TomDLux (Vicar) on Nov 15, 2004 at 16:15 UTC
Have you looked at your web server log and error files and to see what information it recorded when the error occurred? -- `TTTATCGGTCGTTATATAGATGTTTGCA`	[reply]
Re: Perl Seems to be giving me random errors by Anonymous Monk on Nov 15, 2004 at 17:01 UTC
I've seen this happen once, I'm not sure what caused it for sure, but the power supply was going in the machine at the time. A reboot fixed it, and I've never seen it again (the PS was replaced while it was shut down, so I didn't get a chance to test if that was what was causing it or not) Every file on the system when you read it, would randomly show weird characters like you describe. It didn't matter what the file was.	[reply]
Re: Perl Seems to be giving me random errors by Anonymous Monk on Nov 15, 2004 at 18:11 UTC
I contacted the admins who run the server and they sent me back a reply that it was fixed and to let them know if it happens again. It is running fine now. Glad it wasn't something I screwed up. :) Thanks for your help!	[reply]
Re: Perl Seems to be giving me random errors by elwarren (Priest) on Nov 15, 2004 at 22:06 UTC
I remember this type of problem with my 300baud modem on my commodore64. I would have expected that with modern hardware, these types of blips should never even make it to a level where we would be aware of it. Other than the machine informing us of a faulty chip or something. But, my five year old AMD machine started doing the same thing last month, seemingly randomly, then got progressively worse until finally the ReiserFS partition was corrupted and the machine wouldn't boot. Found bad ram chips, replaced them all. Problem is still there. Scrapped the motherboard, cpu, and ram. I know it's off topic from the site, but I was amazed that the problem didn't cause a bigger problem sooner. grumble grumble grumble.	[reply]
Re: Perl Seems to be giving me random errors by chb (Deacon) on Nov 16, 2004 at 07:45 UTC
If I hear about such strange errors, I always check two things: are the connectors on the motherboard and the drives firmly in place, and is the CPU fan running smoothly (a drop of oil can help for some time). Maybe not an option for you, if this happens on a remote server, but anyway...	[reply]