Perl app won't compile /run from cron

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

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Re: Perl app won't compile /run from cron by haukex (Archbishop) on May 23, 2018 at 21:48 UTC
Try the command `perldoc -l Image::Grab` to show you where the module got installed, I'm guessing that that path isn't one of the `@INC` directories listed at the top of your post. Setting the right `PATH` isn't always enough if you've got custom entries added to @INC via something like the `PERL5LIB` environment variable, because then that environment variable needs to be set in the environment that `cron` provides to the programs it runs. I'm still just guessing, but probably that isn't the case and the environment provided by `cron` is different from the one you have on the command line. For example, are you using local::lib? If you want to see the difference, try running this command from both the command line and from a `crontab` entry: `perl -le 'die "$ENV{PERL5LIB} @INC\n"'` If those are different, then it depends on how you're changing `@INC` for the best way to solve this. If you could report back with the results of the above, we can probably help more.	[reply] [d/l] [select]
Re^2: Perl app won't compile /run from cron by dazz (Beadle) on May 25, 2018 at 08:35 UTC
Hi I tried `perldoc -l Image::Grab` but I don't have perldoc installed. I am not using local::lib. I used the cron commmand `* * * * * /usr/bin/perl /home/user/perl_script.pl 1 2>&1 \| /usr/bin/ +logger -t test_cron` [download] to get the compiler error output from syslog. Dazz	[reply] [d/l] [select]
Re^3: Perl app won't compile /run from cron by haukex (Archbishop) on May 25, 2018 at 12:17 UTC
I am not using local::lib. Based on the pathname `~/perl5/lib/perl5` and that you say you used `cpan` to install the module, I'm pretty sure you are using local::lib. The `cpan` client, when run without `sudo`, will usually detect that it doesn't have permissions to write to the system directories and autoconfigure to use local::lib. If you check your `.profile` or `.bashrc` files, you should see variables like `PERL_LOCAL_LIB_ROOT` and `PERL5LIB` being set there, these would have been added there by local::lib, and as I said those are the variables that are probably missing from the environment that `cron` provides, hence my suggestion to try and set `PERL5LIB` explicitly. I tried `perldoc -l Image::Grab` but I don't have perldoc installed. Well, you could do `sudo apt-get install perl-doc`, but did you try dave_the_m's suggestion, which should work even without `perldoc`? I also made a few other suggestions and asked a few questions above as well as here.	[reply] [d/l] [select]
Re^3: Perl app won't compile /run from cron by hippo (Bishop) on May 25, 2018 at 09:56 UTC
I tried `perldoc -l Image::Grab` but I don't have perldoc installed. `locate Image/Grab.pm`	[reply] [d/l] [select]
Re: Perl app won't compile /run from cron by dave_the_m (Monsignor) on May 23, 2018 at 21:49 UTC
Perl usually gets extra module paths from the PERL5LIB environment variable rather than PATH. So that would be the first thing to look at. Also, its possible that cron and the terminal are running as different users (and so with different file/directory permissions), or are using different versions of the perl executable. You can see where the module is being loaded from the terminal by using: `$ perl -le 'require Image::Grab; print $INC{"Image/Grab.pm"}' /some/path/lib/Image/Grab.pm` [download] If that path isn't in the list of paths in the cron error message, that's another place to investigate. Dave.	[reply] [d/l]
Re^2: Perl app won't compile /run from cron by haukex (Archbishop) on May 23, 2018 at 21:52 UTC
... or are using different versions of the perl executable. Excellent points, and that reminds me of another piece of advice I've learned the hard way (a few times `;-)` ): Always use absolute paths in `crontab`.	[reply] [d/l] [select]
Re: Perl app won't compile /run from cron by choroba (Cardinal) on May 23, 2018 at 22:20 UTC
Perl modules are searched for in `@INC`, not `$ENV{PATH}`. To set @INC, you can use the `$PERL5LIB` environment variable, or specify the directories with the `-I` options to `perl` (see perlrun). ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l] [select]
Re: Perl app won't compile /run from cron by haukex (Archbishop) on May 24, 2018 at 12:37 UTC
Crossposted to StackOverflow. Crossposting is acceptable, but it is considered polite to inform about it so that efforts aren't duplicated.	[reply]
Re: Perl app won't compile /run from cron by Random_Walk (Prior) on May 24, 2018 at 08:44 UTC
It looks like you are missing the path to your library in your `@INC` array within Perl. You can add a line to your script to explicitly use the library directory where `Image::Grab` is installed. `use lib '/var/local/perl-site/';` [download] Or where ever it may be. It is strange that it is not in a standard system patch though if it is installed with cpan. Do you know the directory where `Grab.pm` is installed? Cheers, R. Pereant, qui ante nos nostra dixerunt!	[reply] [d/l] [select]
Re^2: Perl app won't compile /run from cron by dazz (Beadle) on May 24, 2018 at 11:05 UTC
Hi Grab is located: `darren@trackcam3:~ $ find ~/ -name Grab /home/darren/.cpan/build/Image-Grab-1.4.2-gwMQYz/lib/Image/Grab /home/darren/.cpan/build/Image-Grab-1.4.2-gwMQYz/blib/lib/Image/Grab /home/darren/.cpan/build/Image-Grab-1.4.2-gwMQYz/blib/lib/auto/Image/G +rab /home/darren/.cpan/build/Image-Grab-1.4.2-gwMQYz/blib/arch/auto/Image/ +Grab /home/darren/perl5/lib/perl5/arm-linux-gnueabihf-thread-multi-64int/au +to/Image/Grab /home/darren/perl5/lib/perl5/Image/Grab` [download] Image::Magick is installed here: `/usr/lib/arm-linux-gnueabihf/perl5/5.24/Image/Magick /usr/lib/arm-linux-gnueabihf/perl5/5.24/auto/Image/Magick` [download] This is a headless server so having libraries splattered around isn't helpful. Looking back at my notes, CPAN installed the modules in my home dir. The Ubuntu packages were installed in /usr. Dazz	[reply] [d/l] [select]
Re^3: Perl app won't compile /run from cron by marto (Cardinal) on May 24, 2018 at 11:19 UTC
"This is a headless server so having libraries splattered around isn't helpful" Then don't do that. If you are using the system perl and a package is available in apt, use that, otherwise you need to install things in the right place (`sudo cpanm Image::Grab`), or (as detailed in other replies you already have) specify the correct paths for your cron jobs for where you have installed things.	[reply] [d/l]
Re^4: Perl app won't compile /run from cron by dazz (Beadle) on May 24, 2018 at 22:56 UTC
Re^5: Perl app won't compile /run from cron by huck (Prior) on May 24, 2018 at 23:25 UTC
Re^5: Perl app won't compile /run from cron by marto (Cardinal) on May 25, 2018 at 05:28 UTC
Some notes below your chosen depth have not been shown here
Re: Perl app won't compile /run from cron by marto (Cardinal) on May 24, 2018 at 08:46 UTC
You've posted this many times now, I suspect you are refreshing your screen and resubmitting a form. Your first post has responses.	[reply]
Re^2: Perl app won't compile /run from cron by LanX (Saint) on May 24, 2018 at 10:32 UTC
I already messaged him yesterday, telling him not to refresh. I think it's deliberate. Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :) Wikisyntax for the Monastery}	[reply]
Re^2: Perl app won't compile /run from cron by dazz (Beadle) on May 24, 2018 at 10:52 UTC
Hi I have been refreshing my screen looking for responses. I had no idea a refresh caused a resubmit. I have only just found this message and the responses. I don't visit this site very often so still learning its quirks. Dazz	[reply]
Re^2: Perl app won't compile /run from cron by Anonymous Monk on Jun 01, 2018 at 21:45 UTC
I suspect you are refreshing your screen and resubmitting a form. As users have been trained to do. pmdev should simply use POST/REDIRECT/GET like they're supposed to	[reply]
Re: Perl app won't compile /run from cron by dazz (Beadle) on May 24, 2018 at 09:43 UTC
Hi The problem I have is exactly the same as this link https://stackoverflow.com/questions/17194632/perl-cant-find-module-when-run-from-cron-daily I have found the Image::Grab module at `~/perl5/lib/perl5/Image` [download] The directory: `:/usr/lib/perl5` [download] is empty and so is `:/usr $ ls lib/perl5/` [download] I am running Rasbian on a Raspberry Pi. I don't know what files are supposed to be where. Dazz	[reply] [d/l] [select]
Re^2: Perl app won't compile /run from cron by haukex (Archbishop) on May 24, 2018 at 10:05 UTC
Sounds like the module was installed with local::lib, which should normally set its environment variables in `.profile`/`.bashrc`. Anyway, did you try the solutions suggested in that link? For example prepending `PERL5LIB=/home/pi/perl5/lib/perl5` to the command in your `crontab`?	[reply] [d/l] [select]
Re^3: Perl app won't compile /run from cron by dazz (Beadle) on May 24, 2018 at 11:16 UTC
Hi The "missing" modules were installed with CPAN that has chosen to put them in my home dir. Dazz	[reply]
Re^2: Perl app won't compile /run from cron by marto (Cardinal) on May 24, 2018 at 09:46 UTC
Did you read the responses to your first post: Perl app won't compile /run from cron?	[reply]


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