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User Questions
octal number mysteriously changes after pass to subroutine
2 direct replies — Read more / Contribute
by Anonymous Monk
on Feb 01, 2023 at 13:56
    Dear Monks, I'm passing an octal file mode to a sub like sub(0666) but in the sub I'm seeing it as 438, and 0777 becomes 511. Quoting the mode causes it to lose the leading zero so that sub(q(0666)) becomes 666. I can put the leading 0 back and continue but that feels messy. Why is 0666 changing to 438? Thank you!
Parsing error
5 direct replies — Read more / Contribute
by MoodyDreams999
on Jan 30, 2023 at 13:01
    I keep running into an uninitialized error that doesnt make sense to me, I should be writing the state in column 6, but I keep getting Use of uninitialized value $t6 in string eq at Project1_6.pl line 48, <FH> line 2551. Use of uninitialized value $t6 in string eq at Project1_6.pl line 42, <FH> line 2552. Used perl c- it runs, says syntax is okay I tried declaring $t in line 35, "$worksheet->write($rowCount1+1, $_, my $t$_);" Perl C- said that was okay, but I get "syntax error at Project1_6.pl line 37, near "$t[""
    use Excel::Writer::XLSX; use strict; use warnings; my $rowCount = 0; my $filename = "Output2022.xlsx"; my $workbook = Excel::Writer::XLSX->new( $filename ); open(FH, "<", "SRC185.xlsx" ) or die; my $worksheet = $workbook->add_worksheet('List'); $worksheet->write(0, 0, "source_id" ); $worksheet->write(0, 1, "first_name" ); $worksheet->write(0, 2, "middle" ); $worksheet->write(0, 3, "last_name" ); $worksheet->write(0, 4, "address1" ); $worksheet->write(0, 5, "city"); $worksheet->write(0, 6, "state"); $worksheet->write(0, 7, "postal_code"); $worksheet->write(0, 8, "phone_number"); $worksheet->write(0, 9, "address3"); $worksheet->write(0, 10,"province"); $worksheet->write(0, 11, "email"); my $rowCount1 = 0; my $t=0; my @z = 90005; while (<FH>){ chomp; my @t=(',',$_); if(defined($t[8])){ my $Count=0; $worksheet->write($rowCount1+1, $_, $t[$_]); $Count++; } elsif($t[6] eq "CA" && $t[7] eq !defined) { $worksheet->write($rowCount1+1, 7, $z[7]); } $rowCount1++; } $workbook->close(); close(FH);
Seeking a way to access a network user's ID
2 direct replies — Read more / Contribute
by TorontoJim
on Jan 29, 2023 at 06:56
    Can a lady or gentleman please help me find the correct resource. I am looking for information that I can use in an app I'm building.

    It will be run on a LAN behind a firewall. It would be far more convenient if the user could be logged in automatically if they are already logged in to the network it is running on. So, I'm seeking information on accessing a network users's userid and login status. I'm not looking for specific code, just guidance to the proper keywords or terms that I need to research to achieve this end goal, if it is even possible.

    I don't mind doing the legwork, I just don't know what the specific legwork is that I must do right now.

    Peace,
Why don't some CPAN modules append perllocal?
3 direct replies — Read more / Contribute
by Anonymous Monk
on Jan 28, 2023 at 21:15
    perl -MExtUtils::Installed -le '$_=ExtUtils::Installed->new->modules;p +rint'
    1650
    perl -le '@_=grep/Module/,split/\n/,`perldoc -uT perllocal`;print scal +ar@_'
    1472
    perl -MExtUtils::Installed -le '@_=ExtUtils::Installed->new->modules;p +rint for sort{lc$a cmp lc$b}@_' >mod.ext perl -e '@_=grep/Module/,`perldoc -uT perllocal`;for(@_){s/.*?\|([^>]+ +)>/$1/}print for sort{lc$a cmp lc$b} @_' >mod.loc diff -y mod.ext mod.loc

    diff -y mod.ext mod.loc|grep '<'|wc -l
    232
    diff -y mod.ext mod.loc|grep '>'|wc -l
    54
What to test in a new module
3 direct replies — Read more / Contribute
by Bod
on Jan 28, 2023 at 17:16

    I've created a helper function for my own purposes and thought it would be useful to others. So CPAN seems a sensible place to put it so others can use it if they want to...

    It's function is simple - to go to the homepage of a website and return an array of URI's within that site, being careful not to stray outside it, that use the http or https scheme. It ignores things that aren't plain text or that it cannot parse such as PDFs or CSS files but includes Javascript files as links (thing like window.open or document.location.href) might be lurking there. It deliberately doesn't try to follow the action attribute of a form as that is probably meaningless without the form data.

    As the Monastery has taught be that all published modules should have tests, I want to do it probably and provide those tests...

    But, given that there is only one function and it makes HTTP requests, what should I test?

    The obvious (to me) test is that it returns the right number of URIs from a website. But that number will likely change over time, so I cannot hardcode the 'right' answer into the tests. So beyond the necessary dependencies and their versions, I'd like some ideas of what should be in the tests, please.

    In case you're interested, this came about from wanting to automate producing and installing sitemap files.

Any reference about %SIG
3 direct replies — Read more / Contribute
by exilepanda
on Jan 28, 2023 at 03:56
    I want to study more on SIGNAL. But after half hour digging, there's nothing useful. I am looking some full documentation that explains

    $SIG{__DIE__} will fire when die() happen
    $SIG{INT} will fire when Ctrl-C pressed
    ...

    Is that anything like this exists?

Can't locate module in @INC when executing script over SSH
1 direct reply — Read more / Contribute
by Leudwinus
on Jan 27, 2023 at 13:55

    I have the following script (json_test) on a remote FreeBSD virtual machine which runs fine when executed directly on the VM:

    #!/usr/bin/env perl use lib "/home/user/perl5/lib"; use JSON; # line 4 print JSON->new->pretty->encode( { qw( a b ) } );

    However, I get the following error message when I try to run it via SSH from my local machine:

    leudwinus@localmachine:~$ ssh user@remotemachine './json_test' Can't locate JSON.pm in @INC (you may need to install the JSON module) + (@INC contains: /home/user/perl5/lib /usr/local/lib/perl5/site_perl/ +mach/5.32 /usr/local/lib/perl5/site_perl /usr/local/lib/perl5/5.32/mach /usr/loc +al/lib/perl5/5.32) at ./json_test line 4. BEGIN failed--compilation aborted at ./json_test line 4.

    Any suggestions on how I can execute this script remotely via SSH?

    On the virtual machine, I get the following information:

    user@remotemachine:~$ perldoc -l JSON /home/user/perl5/lib/perl5/JSON.pm user@remotemachine:~$ perl -V Summary of my perl5 (revision 5 version 32 subversion 1) configuration +: ... @INC: /home/user/perl5/lib/perl5/5.32.1/amd64-freebsd-thread-multi /home/user/perl5/lib/perl5/5.32.1 /home/user/perl5/lib/perl5/amd64-freebsd-thread-multi /home/user/perl5/lib/perl5 /home/user/perl5/lib/perl5/5.32.1/amd64-freebsd-thread-multi /home/user/perl5/lib/perl5/5.32.1 /home/user/perl5/lib/perl5/amd64-freebsd-thread-multi /home/user/perl5/lib/perl5 /usr/local/lib/perl5/site_perl/mach/5.32 /usr/local/lib/perl5/site_perl /usr/local/lib/perl5/5.32/mach /usr/local/lib/perl5/5.32

    JSON is installed on my local Ubuntu machine at /home/leudwinus/perl5/lib/perl5/JSON.pm but I didn't think that would matter.

    Thanks in advance!

CGI Webserver In Perl?
3 direct replies — Read more / Contribute
by sectokia
on Jan 26, 2023 at 18:52

    Hi monks,

    I have a large amount of legacy CGI Perl scripts, which were made to be executed by Apache modperl.

    What I want to do is move to a http server inside a perl script (like AnyEvent::HTTPD) that supports calling the perl CGI scripts - and then package the entire thing as a single exe using par. This is so users can run it without having to have either apache or perl installed.

    Now CGI seems fairly straight forward (content to STDIN, headers to ENV, and STDOUT is the HTTP response), but I figured someone has probably done this before? Or are there better ideas?

    I am essentially doing this to execute the cgi in the httpd request callback:

    { local *STDOUT; local *STDIN; #local %ENV; #$ENV{http-cookie} = $requestCookie; open(STDIN, "<", \$requestBody); open (STDOUT, '>>', \$response); do './cgi/foobar.pl'; }
help with "symbol lookup error" message
3 direct replies — Read more / Contribute
by Special_K
on Jan 26, 2023 at 13:20

    I have the following code:


    #!/tool/bin/perl -w use lib '/home/user_foo/perl_modules/lib/perl5'; use List::MoreUtils qw(uniq); my @test_array = qw(1 2 3 4 4 4 4); my @uniq_test_array = uniq(@test_array); printf("\@uniq_test_array = @uniq_test_array\n");

    The output is as follows (as expected):


    @uniq_test_array = 1 2 3 4

    Now if I add another module reference (File::Copy) to the top of the file like so:


    #!/tool/bin/perl -w use lib '/home/user_foo/perl_modules/lib/perl5'; use List::MoreUtils qw(uniq); use File::Copy;

    I receive the following error message:


    /tool/bin/perl: symbol lookup error: /home/user_foo/perl_modules/lib/p +erl5/x86_64-linux/auto/List/Util/Util.so: undefined symbol: Perl_gv_i +nit

    The error references the List::Util module, but doesn't occur unless I add the "use File::Copy", which is a completely separate module. What is going on here?

Script exponentially slower as number of files to process increases
5 direct replies — Read more / Contribute
by xnous
on Jan 25, 2023 at 15:04
    Hello, monks. With your help I've written a script that processes a large number of text files, efficiently. I run this script inside directories containing 1K to 10K files, usually less than 5K.

    However, I've noticed that attempting to process larger number of files, i.e. several directories at once, the script gets exponentially slower. For example, while a run on 3.5K files would takes around 4.5 seconds, on 35K files takes 90 instead of 45 seconds and on 350K files it runs for hours.

    This has baffled me, as I'm using subdirectories to organize the data, and filesystem operations shouldn't impact performance negatively; additionally, the data filenames are glob()bed into an array which is looped over and not slurped in at once and processed in bulk (although, in my tests I tried that approach which exhibited the same behavior).

    What's very interesting is that when I put a counter to stop processing at 1000 files, I got increasingly longer processing times with each subdirectory added to the list, despite only processing 1000 files from it. Also, I always copy my data to /tmp which is mounted as tmpfs to reduce SSD wear and achieve maximum read/write performance. Testing:

    wget http://www.astro.sunysb.edu/fwalter/AST389/TEXTS/Nightfall.htm html2text-cpp Nightfall.htm >nightfall.txt mkdir 00; for i in `seq -w 0 3456`; do head -$((RANDOM/128)) nightfall +.txt >00/data-$i; done
    This will create a directory ("00") with 3,456 random sized files inside. Perl script:
    #!/usr/bin/perl use strict; use warnings; use 5.36.0; use Env; use utf8; use POSIX "sys_wait_h"; #for waitpid FLAGS use Time::HiRes qw(gettimeofday tv_interval); use open ':std', ':encoding(UTF-8)'; my $benchmark = 1; # print timings for loops my $TMP='/tmp'; my $HOME = $ENV{HOME}; my $IN; my $OUT; my @data = glob("data-* ??/data-*"); my $filecount = scalar(@data); die if $filecount < 0; say "Parsing $filecount files"; my $wordfile="data.dat"; truncate $wordfile, 0; #$|=1; # substitute whole words my %whole = qw{ going go getting get goes go knew know trying try tried try told tell coming come saying say men man women woman took take lying lie dying die }; # substitute on prefix my %prefix = qw{ need need talk talk tak take used use using use }; # substitute on substring my %substring = qw{ mean mean work work read read allow allow gave give bought buy want want hear hear came come destr destroy paid pay selve self cities city fight fight creat create makin make includ include }; my $re1 = qr{\b(@{[ join '|', reverse sort keys %whole ]})\b}i; my $re2 = qr{\b(@{[ join '|', reverse sort keys %prefix ]})\w*}i; my $re3 = qr{\b\w*?(@{[ join '|', reverse sort keys %substring ]})\w*} +i; truncate $wordfile, 0; my $maxforks = 64; print "maxforks: $maxforks\n"; my $forkcount = 0; my $infile; my $subdir = 0; my $subdircount = 255; my $tempdir = "temp"; mkdir "$tempdir"; mkdir "$tempdir/$subdir" while ($subdir++ <= $subdircount); $subdir = 0; my $i = 0; my $t0 = [gettimeofday]; my $elapsed; foreach $infile(@data) { $forkcount -= waitpid(-1, WNOHANG) > 0 while $forkcount >= $maxfor +ks; # do { $elapsed=tv_interval($t0); print "elapsed: $elapsed\n"; die; + } if $i++ >1000; # 1000 files test $i++; # comment out if you uncomment the above line $subdir = 1 if $subdir++ > $subdircount; if (my $pid = fork) { # $pid defined and !=0 -->parent ++$forkcount; } else { # $pid==0 -->child open my $IN, '<', $infile or exit(0); open my $OUT, '>', "$tempdir/$subdir/text-$i" or exit(0); while (<$IN>) { tr/-!"#%&()*',.\/:;?@\[\\\]_{}><^)(|/ /; # no punct " s/^/ /; s/\n/ \n/; s/[[:digit:]]{1,12}//g; s/w(as|ere)/be/gi; s{$re2}{ $prefix{lc $1} }g; # prefix s{$re3}{ $substring{lc $1} }g; # part s{$re1}{ $whole{lc $1} }g; # whole print $OUT "$_"; } close $OUT; close $IN; defined $pid and exit(0); # $pid==0 -->child, must exit itself } } ### now wait for all children to finish, no matter who they are 1 while wait != -1; # avoid zombies this is a blocking operation local @ARGV = glob("$tempdir/*/*"); my @text = <>; unlink glob "$tempdir/*/*"; open $OUT, '>', $wordfile or die "Error opening $wordfile"; print $OUT @text; close $OUT; $elapsed = tv_interval($t0); print "regex: $elapsed\n" if $benchmark;
    Add more directories to process:

    for dir in $(seq -w 01 10); do cp -a 00 $dir; done

    Any help and insight will be greatly appreciated.


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