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Help converting to a Windows service
1 direct reply — Read more / Contribute
by bajangerry
on Mar 23, 2017 at 14:42

    Hello Monks

    EDIT: Ok so I may have been misleading everyone. I have been able to install the script as a service but for some reason I get an error when running it as a service. What runs perfectly from a command line fails as a service with the below error:

    Error 1053: The service did not respond to the start or control request in a timely fashion

    I have been trying to wrap my head around using Win32::Daemon to have a perl script and/or pp converted executable of the same script run as a service and I can't seem to figure out how this is done. I have tried using the Windows "sc create..." command with the .exe file but that does not work so I am obviously missing the Win32::Daemon portion in the script

    The script simply monitors a network stream and based on the output it will write to a file, see below

    #!/usr/bin/perl use strict; use IO::Socket; use POSIX; use warnings; use Config::Simple; use Win32::Daemon; sub logMonitor{ #subrouting to connect to the PBX log and monitor for +the Emergency calls my ($HOST, $PORT)= @_; OUTER: if (my $sock = new IO::Socket::INET(PeerAddr => $HOST, Peer +Port => $PORT,Proto => "tcp",)) { while (<$sock>) { s/^\0+//; # Remove leading null characters chomp ($_); my $data = substr($_, 1,17); my $event = substr ($data, 2,1); my $hr = substr ($data, 3,2); my $min = substr ($data,5,2); my $year = substr($data, 9,4); my $mon = substr($data, 13,2); my $day = substr ($data,15,2); #print "$hr:$min on $year-$mon-$day \n"; if ($event eq "A") { my $agent = substr($_, 17,4); # print "\n Agent $agent logged in \n" ; my $output = "Agent $agent logged in at $hr:$min on ex +t $year"; filePrint($output); } } else { print "Failed to connect to $HOST on $PORT. Will retry in a mi +nute.\n"; sleep 60; goto OUTER; } } #End of monitor subroutine sub filePrint{ #write data to file with date and time stamp my ($DATA)= @_; print "$DATA\n"; my $dateStamp = strftime '%Y-%m-%d', localtime; my $file = "$dateStamp.log"; my $timeStamp = strftime '%H:%M:%S', localtime; if (-f $file){ open (my $fh,'>>', $file); print $fh "$timeStamp | $DATA\n"; close $file; } else { open (my $fh,'>', $file); print $fh "$timeStamp | $DATA\n"; close $file; } }# End of filePrint routine my $cfg = new Config::Simple(); $cfg->read('config.ini'); my $HOST = $cfg->param("pbx"); my $PORT = $cfg->param("port"); logMonitor($HOST, $PORT); #Open the log monitoring subroutine

    Can anyone explain to me how to use Win32::Daemon with this script to create a service from it? Right now it will run as a command line tool

    many thanks!

DateTime::Format::Flexible; for Log Parse with multiple formatted lines
2 direct replies — Read more / Contribute
by TCLion
on Mar 23, 2017 at 13:54

    Basic Info:Log is in text lines. I am combining all lines and breaking it up to separate tags/lines. The Log files are copies and not being updated currently for development.

    Trying to figure out the best way to get my time from lines in log files. Parsing the line for date time error and error message to output to csv. This process is working on some of my log files but one in particular has 2 different time/date formats. For this reason the code is not picking up the lines not formatted the specific way.

    This line is ok format:
    2017-02-20T09:30:53.177000 20[] 0000000000000000 Error Description

    Second (problem)line
    Mon Feb 20 09:31:25 2017 INFO AGENTEXEC Error Description

    Since I now have 2 formats in 1 log I now have installed DateTime::Format::Flexible. Hoping this will fix my issue and convert one format to match the other.

    #Original Working code prior to 2nd date format #!/usr/bin/perl use IO::File; my $file = 'file.location.log'; open(MYLOG, "<$file") or die "Can't open $file: " . $!; my @mylog = <MYLOG>; close(MYLOG); my $myfixedlog = join("ENDOFLINE", @mylog); # Date 1 ,T 2, Tim +e 3 , 4, 5 , 6 , 7 , + 8 , 9 while ($myfixedlog =~ /([0-9]{4}-[0-9][0-9]-[0-9][0-9])(T)([0-9][0-9]: +[0-9][0-9]:[0-9][0-9])(.\d+\s\d+.\d+.\s)(.{16}\s)(\[\w+\])(\w+\S\s+)( +.+?)(ENDOFLINE)/smg) { $date = $1; $severity = $7; $timestamp = $3; $errormsg = $6; chomp($errormsg); print "New Error Found...\n"; print "0 $0\n"; print "1 $1\n"; print "2 $2\n"; print "3 $3\n"; print "4 $4\n"; print "5 $5\n"; print "6 $6\n"; print "7 $7\n"; print "8 $8\n"; print "9 $9\n"; }

    That was to get the positions for the output.
    Then to get the desired output using this code.

    use 5.18.0; use warnings; use IO::File; use Time::Piece; my $servername = "Server1"; # This is the Location of the Original Log File my $OLF = '\\\server\logs\server.log'; # This is the location of the file parsed my $file = 'server.log'; open(MYLOG, "<$file") or die "Can't open $file: " . $!; my @mylog = <MYLOG>; close(MYLOG); # This is the Location\Name of the file Being Created my $CSVLOG = 'output.csv'; open(OUTLOG, ">>$CSVLOG") ; my @outlog = <OUTLOG>; my $runtimestamp = localtime(time); my $myfixedlog = join("ENDOFLINE", @mylog); print OUTLOG "$OLF\n"; print OUTLOG "Server, Date, TimeStamp, Severity, ErrorMsg, \n"; # Date 1 ,T 2, Tim +e 3 , 4, 5 , 6 , 7 , 8 + , 9 while ($myfixedlog =~ /([0-9]{4}-[0-9][0-9]-[0-9][0-9])(T)([0-9][0-9]: +[0-9][0-9]:[0-9][0-9])(.\d+\s\d+.\d+.\s)(.{16}\s)(\[\w+\])(\w+\S)(.+? +)(ENDOFLINE)/smg) { my $date = $1; my $timestamp = $3; my $severity = $7; my $errormsg = join "",$6, $7, $8; chomp($errormsg); if ($errormsg =~ /DfException/ || $severity eq "error +:" || $errormsg =~ /started in/){ foreach ($errormsg =~ /DfException/ || $seve +rity eq "error:" || $errormsg =~ /started in/) {print OUTLOG "$servername, $date, $timestam +p, $severity, $errormsg \n"}}; # print OUTLOG "$servername, $da +te, $timestamp, $severity, $errormsg, \n" } print OUTLOG @outlog; close(OUTLOG); print "CSV - File Created Log File: $CSVLOG";

    So now trying to add and use new code but cant figure out how to set the desired format or how to have it collect and identify properly as before from original code. This is the added code I have found so far to the code to find locations for $myfixedlog

    DateTime::Format::Flexible; my $dt = DateTime::Format::Flexible->parse_datetime( $date, lang => [' +en'], );

    Ok so I guess the questions are:
    How to declare $date if its already being used (in code i am not yet familiar with)?
    If this code pulls out the date would it have a position or just be placed by $dt per line?
    If the date is pulled and formatted correctly would I still break up my line the same way?

    Looking at the preview it looks like i might have grabbed code for 2 different log files but the basics are the same.
    Any Assistance would be appreciated. And no I did not write the original code but I have modified these listed to work. I am Still new to Perl but it is getting easier the more I do.
    Hopefully this makes sense to someone.

Any reason NV is not marked as POK when accessed as string?
2 direct replies — Read more / Contribute
by vr
on Mar 23, 2017 at 07:22

    Just curious, not a 'problem' which requires solution. Maybe developers thought real numbers stringification is usually approximate, that's why? Or simply nobody cares?

    C:\>perl -MDevel::Peek -e "$x = 0.5; qq/$x/; Dump $x" SV = PVNV(0x38bb4) at 0xd217cc REFCNT = 1 FLAGS = (NOK,pNOK) IV = 0 NV = 0.5 PV = 0xd16014 "0.5"\0 CUR = 3 LEN = 28 C:\>perl -MDevel::Peek -e "$x = 0; qq/$x/; Dump $x" SV = PVIV(0xd200c4) at 0xd2685c REFCNT = 1 FLAGS = (IOK,POK,pIOK,pPOK) IV = 0 PV = 0xd16274 "0"\0 CUR = 1 LEN = 10

    Hence, 'double' is converted to string any time it is required. E.g.:

    use Benchmark qw/ cmpthese /; $x = 42.0; %h = (); cmpthese( -1, { F => sub { $h{ pack 'F', $x } = 1 }, s => sub { $h{ $x } = 1 }, });
    Rate s F s 344025/s -- -86% F 2490475/s 624% --

    I found that one my little application, which maintains kind of 'seen' hash, gets nice boost if hash keys are packed as above, instead of 'just used as they are'. Actually, keys are pixels coordinates, they became real numbers because library I use returns them so. Pixels are usually aplenty and hash is accessed a lot, therefore speed gain was significant. But of course it would be even faster if PV was added on first access and POK was set, i.e. without packing.

Parse string and extract word after specific pattern
5 direct replies — Read more / Contribute
by rinkish85
on Mar 23, 2017 at 06:49

    Hi, I need to parse the below string


    I am intrested only in part ROLLBACK.check

    Basically I am looking at what appears after "ROLLBACK" in above string.

    for e.g in this case its "check" .... that could be any word string like check2, check3, migration1, migration2.

    Thank you. Please suggest.
Search hash keys using values from array
8 direct replies — Read more / Contribute
by AhmedABdo
on Mar 23, 2017 at 06:36

    Hi dear all
    Assuming I have this array and hash.

    My @array = qw(world today is nice); my %hash = (0 => "Hello", 1=> "world" , 2=> "today" , 3=> "is" , 4=> " +nice" );
    I want to search thought the hash values using the array elements as values and then print the hash keys for each searched value from the array in a new array.
    It should print 1 for world, 2 for today, so on which will be saved in the new array
    I tried to use lookup with loop thought the array but it did not work.
    I used grep also, but did not hot what I want
    Any idea about how I can do it???
    Thanks in advance

SOAP sign more elements
No replies — Read more | Post response
by makita
on Mar 23, 2017 at 04:56
    Hello, does heve anybode experience how to create a signature of more elements via XML::Compile::WSS ::Signature? This is my code:
    my $wsa = XML::Compile::SOAP::WSA->new(version => '1.0'); my $wsdl = XML::Compile::WSDL11->new("some.wsdl"); my $wss = XML::Compile::SOAP::WSS->new(schema => $wsdl); my $cert_obj = Crypt::OpenSSL::X509->new_from_file($cert); my $token = XML::Compile::WSS::SecToken::X509v3->new ( certificate => + $cert_obj,); my $sig = $wss->signature( schema => $wsdl, token => $token, sign_types=>['wsa:Action','wsa:To', 'wsu:Timestamp', 'wsa: +MessageID','SOAP-ENV:Body'], signer=>DSIG_RSA_SHA1, public_key => $cert, private_key =>$cert_pk, );
    My problem is that only 'SOAP-ENV:Body' is always signed as default even i set more types. Inside of source code I've found more parameters like sign_when and sign_put. Don;t know how to use it and documentation is very poor
url get with string
2 direct replies — Read more / Contribute
by bigup401
on Mar 23, 2017 at 04:34

    why if i post like this it doesn't work

    $name = 'john'; my $req = HTTP::Request->new(GET => '$nam +e'); $req->content_type('application/json');

    but it works when no $name string in url

    my $req = HTTP::Request->new(GET => ' +'); $req->content_type('application/json');
Mail - 32bit vs 64bit
3 direct replies — Read more / Contribute
by krausr
on Mar 22, 2017 at 08:57

    I have a script that emails me details from a file. The script works fine in a 32-bit version of Activeperl, but does not run using a 64-bit version. It seems to crap out on this line:

    $smtp->mail($email_from); # sender's address
  • Why would that ever be a case?
  • How can I fix this to work on either version?
  • use Net::SMTP; use Win32::EventLog; $summary = ''; $extra = ''; $begin_summary = 0; $data_file = "C:/Logs/myfile.log"; open(IN, $data_file) || die("Could not open file!"); @raw_data = <IN>; close(IN); for my $row (@raw_data) { if ( $row =~ /\s+Total\s+Copied\s+Skipped\s+Mismatch\s+FAILED\s+Ex +tras\s+/ ) { $begin_summary = 1; } if ( $begin_summary ) { $summary .= $row; } if ($row =~ /\s+Ended \: /) { #print "Exiting loop\n"; last; } } write_event(900, EVENTLOG_INFORMATION_TYPE, $summary); send_email("My Big Fat Notification - " . $ENV{COMPUTERNAME}, "$extra\ +n$summary"); sub send_email() { my ($subject, $body) = @_; my $email_from = ''; my $email_to = (''); my $smtp = Net::SMTP->new(''); # Connect to a +n SMTP server $smtp->mail($email_from); # sender's address $smtp->to($email_to); # Recipient's address $smtp->data(); # Start the mail # Send the header. $smtp->datasend("To: $email_to\n"); $smtp->datasend("From: $email_from\n"); $smtp->datasend("Subject: $subject\n"); $smtp->datasend("\n"); MORE CODE AFTER THIS...
Accessing the hash name in perl
5 direct replies — Read more / Contribute
by Sonali
on Mar 22, 2017 at 08:11

    Hello Perl monks,

    I am a Perl newbie

    I am try to get the name of the hash which is in another Perl file, and then access the hash elements, but when I run my program I am getting these errors

    Use of uninitialized value $line in pattern match (m//) at line 17.

    Use of uninitialized value $typ_s in string at line 20.

    My code goes like this

    package hash; use strict; use warnings; $test = { 'hash1' => { 'paramA' => '00' , 'paramB' => 'FF' , }, 'hash2' => { 'paramA' => '01' , 'paramB' => '02' , }, 'hash3' => { 'paramA' => '00' , 'paramB' => '03' , }, };

    This hash structure is generated, so I can't modify it

    This the Perl file which contains the hash that needs to be extracted

    This is the Perl script I have written to extract the hash

    #!/usr/local/bin/perl use strict; use warnings; Generate(); sub Generate { Process_File(''); } sub Process_File { my $filename = shift; open(my $fh, '<:encoding(UTF-8)', $filename) or die "Could not open file '$filename' $!"; my $line; $line =~ m/\'hash1\'/; my $typ_s = $line->{paramA}; my $paramB = $line->{paramB}; print "$typ_s"; }

    Help me!

CPAN::Mini on a diet
2 direct replies — Read more / Contribute
by glasswalk3r
on Mar 21, 2017 at 19:14

    Hello follow monks,

    Are you aware of any technique to reduce the size of a CPAN::Mini repository?

    I was checking my local mirror here and it is around 4.9Gb on a OpenBSD 6 box with FFS.

    Taking a look at my ID under authors directory, I see that there are tarballs over there that are not even listed on my PAUSE account anymore (might be some issue regarding mirror synchronization). Anyway, I guess that for my purposes I could use only the latest available distribution for everybody.

    A quick check on CPAN::Mini and minicpan documentation doesn't show anything that would help with that.

    Is there any trick to take care of it?



    I tried this:

    Still pending to validate if it didn't break anything...

    Anyway, I was able to reduce it to 3.0Gb from the initial 4.9Gb...

    Alceu Rodrigues de Freitas Junior
    "You have enemies? Good. That means you've stood up for something, sometime in your life." - Sir Winston Churchill
Directory Structure Recommendations
3 direct replies — Read more / Contribute
by Ossie
on Mar 20, 2017 at 08:14

    Hi Folks

    As a newbie to Perl I'm seeking guidance about directory structure that is good practice, as I've not yet found it in the various documents I've looked at.

    My primary objective is to run a program (Mapivi) under Perl on a Windows PC (I'll write my own additional code at later stage).

    I've successfully installed Strawberry Perl and downloaded Mapivi together with other necessary files such as Perl/Tk and Image-MetaData-JPEG.

    So what (if any) additional directories should I create to hold the various files when I unpack them, prior to running the usual sequence of Makefile & Test & Install, and should the resulting files be put into specific directories?

    If there are existing publications covering this then I'd be grateful if you point me in their direction, as well as giving the benfit of your experience.

    Related follow-on questions may then be about what has to be manually added to PATH and @INC


how to align the label and entry text box in my tk GUI
9 direct replies — Read more / Contribute
by fsmendoza
on Mar 20, 2017 at 03:22

    Dear Perlmonk experts,

    I'm designing my simple GUI and i could not find a way to get rid of the spaces between the label and entry box in my output GUI and align them. Please advice on what will be the best way to do this.

    Thank you.

    use strict; # module to must always declare variabl +es before you use them use warnings; # module to show where is the error use Tk; # module for the Windows GUI my $mainwindow = MainWindow->new(); $mainwindow->geometry("600x150"); $mainwindow->title("Window"); # Disable the window Resize $mainwindow->resizable(0,0); # Menu display option my $main_menu = $mainwindow->Menu(); $mainwindow->configure(-menu => $main_menu); #File my $file_menu = $main_menu->cascade(-label=>"File", -underline => 0, - +tearoff=>0); $file_menu->command(-label=>"New", -underline=>0, -command=>sub{exi +t}, -state => 'disabled'); $file_menu->command(-label=>"Exit", -underline=>0, -command=>sub{ex +it}); # About $main_menu->command(-label=>"About", -command=>sub{$mainwindow->messag +eBox(-title=> "About", -message=>"Version 3.0.0", -type => "ok")}); # text variable my $label_firstname; my $entry_firstname; my $label_lastname; my $entry_lastname; my $label_loginid; my $entry_loginid; my $button_add; # -anchor => 'e' | 'w' | 'n' | 's' | 'ne' | 'nw' | 'se' | 'sw' | 'cen +ter' # top ################################ # nw n ne # # # # w center e # # # # sw s se # ################################ # bottom $label_firstname = $mainwindow->Label(-text => 'Firstname:')->pack (-a +nchor => 'nw'); $entry_firstname = $mainwindow->Entry(-width => 35,-text => 'Firstname +')->pack (-anchor => 'n' ); $label_lastname = $mainwindow->Label(-text => 'Lastname:')->pack (-anc +hor => 'nw'); $entry_lastname = $mainwindow->Entry(-width => 35,-text => 'Lastname') +->pack (-anchor => 'n'); $label_loginid = $mainwindow->Label(-text => 'Login ID:')->pack( -anch +or => 'nw'); $entry_loginid = $mainwindow->Entry(-width => 35,-text => 'loginID')-> +pack (-anchor => 'n'); $button_add = $mainwindow->Button(-text => 'Add New User', -command=>s +ub{exit})->pack(-anchor => 'se'); MainLoop();
New Meditations
OT: Got fired this week
9 direct replies — Read more / Contribute
by karlgoethebier
on Mar 23, 2017 at 05:43

    As i'm aged 60 + i guess i'll never get a new job. I think i need to face retirement. I first thought to delete my account on PM and through away all the code i ever wrote as well as my hand library and forget about everything related to programming. But it isn't so easy. I spent the last 20 years with this stuff. I'll stay a bit here - for fun. And perhaps i'll learn a new programming language ;-)

    Best regards, Karl

    «The Crux of the Biscuit is the Apostrophe»

    Furthermore I consider that Donald Trump must be impeached as soon as possible

New Cool Uses for Perl
Mutex::Flock - Fcntl advisory locking supporting processes and threads.
1 direct reply — Read more / Contribute
by marioroy
on Mar 23, 2017 at 02:59


    Re: Scheduling Perl Tasks

    This is a nice to have module for anybody that wants it. Lately, I lack the time to make a module and publish on CPAN. It is well tested on all supported platfoms including support for threads. It is also optimized, thus low overhead.

    ## Mutex::Flock - Fcntl-based advisory locking. package Mutex::Flock; use strict; use warnings; no warnings qw( threads recursion uninitialized once ); our $VERSION = '0.007'; use Fcntl ':flock'; use Carp (); my $has_threads = $INC{''} ? 1 : 0; my $tid = $has_threads ? threads->tid() : 0; sub CLONE { $tid = threads->tid() if $has_threads; } sub DESTROY { my ($pid, $obj) = ($has_threads ? $$ .'.'. $tid : $$, @_); $obj->unlock(), close(delete $obj->{_fh}) if $obj->{ $pid }; unlink $obj->{path} if ($obj->{_init} && $obj->{_init} eq $pid); return; } sub _open { my ($pid, $obj) = ($has_threads ? $$ .'.'. $tid : $$, @_); return if exists $obj->{ $pid }; open $obj->{_fh}, '+>>:raw:stdio', $obj->{path} or Carp::croak("Could not create temp file $obj->{path}: $!"); return; } ## Public methods. my ($id, $prog_name) = (0); $prog_name = $0; $prog_name =~ s{^.*[\\/]}{}g; $prog_name = 'perl' if ($prog_name eq '-e' || $prog_name eq '-'); sub new { my ($class, %obj) = (@_); if (! defined $obj{path}) { my ($pid, $tmp_dir, $tmp_file) = ( abs($$) ); if ($ENV{TEMP} && -d $ENV{TEMP} && -w _) { $tmp_dir = $ENV{TEMP}; } elsif ($ENV{TMPDIR} && -d $ENV{TMPDIR} && -w _) { $tmp_dir = $ENV{TMPDIR}; } elsif (-d '/tmp' && -w _) { $tmp_dir = '/tmp'; } else { Carp::croak("no writable dir found for temp file"); } $id++, $tmp_dir =~ s{/$}{}; # remove tainted'ness from $tmp_dir if ($^O eq 'MSWin32') { ($tmp_file) = "$tmp_dir\\$prog_name.$pid.$tid.$id" =~ /(.* +)/; } else { ($tmp_file) = "$tmp_dir/$prog_name.$pid.$tid.$id" =~ /(.*) +/; } $obj{_init} = $has_threads ? $$ .'.'. $tid : $$; $obj{ path} = $tmp_file.'.lock'; } # test open open my $fh, '+>>:raw:stdio', $obj{path} or Carp::croak("Could not create temp file $obj{path}: $!"); close $fh; # update permission chmod 0600, $obj{path} if $obj{_init}; return bless(\%obj, $class); } sub lock { my ($pid, $obj) = ($has_threads ? $$ .'.'. $tid : $$, @_); $obj->_open() unless exists $obj->{ $pid }; flock ($obj->{_fh}, LOCK_EX), $obj->{ $pid } = 1 unless $obj->{ $pid }; return; } *lock_exclusive = \&lock; sub lock_shared { my ($pid, $obj) = ($has_threads ? $$ .'.'. $tid : $$, @_); $obj->_open() unless exists $obj->{ $pid }; flock ($obj->{_fh}, LOCK_SH), $obj->{ $pid } = 1 unless $obj->{ $pid }; return; } sub unlock { my ($pid, $obj) = ($has_threads ? $$ .'.'. $tid : $$, @_); flock ($obj->{_fh}, LOCK_UN), $obj->{ $pid } = 0 if $obj->{ $pid }; return; } sub synchronize { my ($pid, $obj, $code, @ret) = ( $has_threads ? $$ .'.'. $tid : $$, shift, shift ); return if ref($code) ne 'CODE'; $obj->_open() unless exists $obj->{ $pid }; # lock, run, unlock - inlined for performance flock ($obj->{_fh}, LOCK_EX), $obj->{ $pid } = 1 unless $obj->{ $p +id }; defined wantarray ? @ret = $code->(@_) : $code->(@_); flock ($obj->{_fh}, LOCK_UN), $obj->{ $pid } = 0; return wantarray ? @ret : $ret[-1]; } *enter = \&synchronize; sub timedwait { my ($obj, $timeout) = @_; local $@; local $SIG{'ALRM'} = sub { alarm 0; die "timed out\n" }; eval { alarm $timeout || 1; $obj->lock_exclusive }; alarm 0; ( $@ && $@ eq "timed out\n" ) ? '' : 1; } 1; __END__ =head1 NAME Mutex::Flock - Fcntl advisory locking =head1 SYNOPSIS { use Mutex::Flock; ( my $mutex = Mutex::Flock->new( path => $0 ) )->lock_exclusive +; ... } { my $mutex = MCE::Mutex::Flock->new( path => $0 ); # terminate script if a previous instance is still running exit unless $mutex->timedwait(2); ... } { use threads; use Mutex::Flock; my $mutex = Mutex::Flock->new; threads->create('task', $_) for 1..4; $_->join for ( threads->list ); } { use MCE::Hobo; use Mutex::Flock; my $mutex = Mutex::Flock->new; MCE::Hobo->create('task', $_) for 5..8; MCE::Hobo->waitall; } sub task { my ($id) = @_; $mutex->lock; # access shared resource print $id, "\n"; sleep 1; $mutex->unlock; } =head1 DESCRIPTION This module implements locking methods that can be used to coordinate +access to shared data from multiple workers spawned as processes or threads. =head1 API DOCUMENTATION =head2 Mutex::Flock->new ( [ path => "/tmp/file.lock" ] ) Creates a new mutex. When path is given, it is the responsibility of t +he caller to remove the file. Otherwise, it establishes a C<tempfile> internally + including removal on scope exit. =head2 $mutex->lock ( void ) =head2 $mutex->lock_exclusive ( void ) Attempts to grab an exclusive lock and waits if not available. Multipl +e calls to mutex->lock by the same process or thread is safe. The mutex will r +emain locked until mutex->unlock is called. The method C<lock_exclusive> is an alias for C<lock>. =head2 $mutex->lock_shared ( void ) Like C<lock_exclusive>, but attempts to grab a shared lock instead. =head2 $mutex->unlock ( void ) Releases the lock. A held lock by an exiting process or thread is rele +ased automatically. =head2 $mutex->synchronize ( sub { ... }, @_ ) =head2 $mutex->enter ( sub { ... }, @_ ) Obtains a lock, runs the code block, and releases the lock after the b +lock completes. Optionally, the method is C<wantarray> aware. my $val = $mutex->synchronize( sub { # access shared resource return 'scalar'; }); my @ret = $mutex->enter( sub { # access shared resource return @list; }); The method C<enter> is an alias for C<synchronize>. =head2 $mutex->timedwait ( timeout ) Blocks until taking obtaining an exclusive lock. A false value is retu +rned if the timeout is reached, and a true value otherwise. my $mutex = MCE::Mutex::Flock->new( path => $0 ); # terminate script if a previous instance is still running exit unless $mutex->timedwait(2); ... =head1 AUTHOR Mario E. Roy, S<E<lt>marioeroy AT gmail DOT comE<gt>> =cut

    Regards, Mario

    Edit: Removed the underscore after the sigil in variables.
    Edit: Updated synopsis and code for construction.
    Edit: Added timedwait method. Completed documentation.

Solaris: make iostat output clearer
1 direct reply — Read more / Contribute
by johngg
on Mar 22, 2017 at 18:49

    This might be useful for sysadmins who manage Solaris servers. The iostat -En command can be used to check for cumulative disk errors but the output is rather dense so it can be difficult to sort the wood from the trees. This script uses Term::ANSIColor to make errors easier to spot.

    use strict; use warnings; use Term::ANSIColor qw{ :constants }; my $rxTriggers = do { my @triggers = ( q{Soft Errors: }, q{Hard Errors: }, q{Transport Errors: }, q{Media Error: }, q{Device Not Ready: }, q{No Device: }, q{Recoverable: }, q{Illegal Request: }, q{Predictive Failure Analysis: }, ); local $" = q{|}; qr{(@triggers)(\d+)} }; my @iostatCmd = qw{ /usr/bin/iostat -En }; open my $iostatFH, q{-|}, @iostatCmd or die qq{open: @iostatCmd |: $!\n}; print q{-} x 60, qq{\n}; while ( not eof $iostatFH ) { my $record; $record .= $_ for map { eof $iostatFH ? () : scalar <$iostatFH> } 1 .. 5; substr $record, 16, 0, RESET; substr $record, 0, 0, BOLD; $record =~ s{$rxTriggers} { $2 eq q{0} ? $1 . GREEN . $2 . RESET : YELLOW . $1 . RED . $2 . RESET }eg; print $record; print q{-} x 60, qq{\n}; } close $iostatFH or die qq{close: @iostatCmd |: $!\n};

    I no longer have a working Solaris box to provide example output but I hope this will be useful for somebody out there.



New Monk Discussion
Prohibit empty nodes
2 direct replies — Read more / Contribute
by hippo
on Mar 23, 2017 at 11:54

    It's a minor annoyance but hopefully an even more minor fix. I suggest that the site code be modified such that entirely empty nodes are automatically rejected. It's a particular time-and-resource waster in the case of anonymous posts as they serve absolutely no value - would anyone dispute this?

    There might conceivably be some argument for allowing empty non-anonymous posts (although what it might be escapes me) so that could be up for debate. If you think these are worth allowing then do please contribute to this thread.

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