Hello all,

I am having some issues with a cgi script that I have written that uses LWP::UserAgent to scrape webpages and the runs through each page using a regex to match content and puts said content into a hash. It also extracts links using HTML::SimpleLinkExtor and follows specified links to run the whole process over again. At the end it puts the information into a database.

This script works like a champ on a page with a small amount of content, but when it is presented with a large amount of content it chokes. This script is run on a web server using CGI. There are no errors in the apache logs, nor is any error presented to the screen.

I will spare everyone here from burning their eyes on my hobbled code, but I have a couple of questions about debugging in this kind of scenario. Does anyone use the strace command on the process id? I tried that. This is what I get:

fcntl64(9, F_GETFL)                     = 0x2 (flags O_RDWR)
fcntl64(9, F_SETFL, O_RDWR|O_NONBLOCK)  = 0
write(9, "GET /ublank/0___files/4155."..., 416) = 416
select(16, [9], NULL, NULL, {180, 0})   = ? ERESTARTNOHAND (To be rest
+arted)
--- SIGTERM (Terminated) ---

[download]

This is really cryptic and starts to scare me after a while. Can anyone recommend maybe other ways of getting low level debugging output from a script? Does this sound like a memory issue? If so, could it be due to poorly written code, or maybe even buggy perl (5.6.1 on Debian)?

I appreciate everyone's help.

Take care,
ghettofinger

In reply to Methods to debug CGI issues by ghettofinger

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