Why is 27 special?
i'm back to fooling around with Mac::iTunes again. i took a week off after the Mac OS X Conference because i had been thinking about it too much. [ side note: never trust an audience. i let them access (through Apache::iTunes) my iTunes (on the G3 projecting the fancy powerpoint on the screen and hooked up to the house sound). i asked them to take turns, but alas. ] tonight i want to get a Perl version of iTunes Publisher off my to-do list, so i start mucking with the parsing bits again. some of the MP3s now live on another partition, and that partition name is a different length than the old one. this means that the 20 fixed bytes between the volume name and the date, which are \000 in every case i looked at, is really 27 - (length of volume name). i can name partitions with names up to 27 characters, but if i go past that it look like it initially works but then gives a warning. what's the deal? what is magic about 27? why not 31? i assume that these are C strings somewhere so the null bytes makes them a nice, even number. i took me quite a while to actually find this problem. Perl is not the best language for bytewise manipulation of binary data. all of that auto-stringy stuff gets in the way. however, C doesn't have hashes out of the box. i'm stuck somewhere in the middle of two equally annoying solutions. :)
What up with the mac
Hello Perhaps someone can fill me in on this one. I am comparing the run time of a perl program I wrote. Using my Mac G4 which has a 1.5 ghz processor and a 1.3 ghz PC computer (processor chip type I don't know but could find out) I am seeing that the Mac takes 14 seconds to complete what the PC does in 6! What's up with that?
Re: What up with the mac
Quoting Brigham Mecham [EMAIL PROTECTED]: Hello Perhaps someone can fill me in on this one. I am comparing the run time of a perl program I wrote. Using my Mac G4 which has a 1.5 ghz processor and a 1.3 ghz PC computer (processor chip type I don't know but could find out) I am seeing that the Mac takes 14 seconds to complete what the PC does in 6! What's up with that? That could be hard to guess without the detailt of your program. Remember There could be other things than the CPU slowing it down. o The operating system (differences in implementation of systemcalls etc) o The amount of memory, the bus speed of the memory. o The file system (if the program finds files i.e) Without knowing anything about the program, it's impossible to tell. -- [EMAIL PROTECTED]
Re: Why is 27 special?
At 3:09 -0500 10/10/02, _brian_d_foy wrote: this means that the 20 fixed bytes between the volume name and the date, which are \000 in every case i looked at, is really 27 - (length of volume name). i can name partitions with names up to 27 characters, but if i go past that it look like it initially works but then gives a warning. what's the deal? what is magic about 27? why not 31? i assume that these are C strings somewhere so the null bytes makes them a nice, even number. Mac volume names are limited to 27 characters. See http://developer.apple.com/techpubs/mac/Files/Files-102.html for a description for the Master Directory Blocks (aka volume information block). If I had to guess, I'd say that the volume name was intended to be 31 characters, and then at the last minute the volume backup date field was added in at the end of the name which reduced the length of the volume name from 31 to 27 characters. Enjoy, Peter. -- I was away for two months and have just returned, and now have 4600 messages to wade through, so sorry for any delays. http://www.interarchy.com/ http://download.interarchy.com/
Re: What up with the mac
What is the script? If you truly think you have an optimization problem on the Mac, then send us the script -- assuming it is of reasonable size. Are you doing something in Perl that is really a Windows-specific task...are you running Perl within Mac OS X or through Fink packages...do you have the same versions of Perl...are you running Perl on OS X or OS 9...do the computers have the same amount of RAM, similar HDs, running one locally vs off a networked HD??? Also, 1.5 GHz Apple?!? Do you mean dual-1.25 GHz Apple? it is difficult to even comment with so little information to go by. On 2002.10.9, at 12:31 午後, Brigham Mecham wrote: Hello Perhaps someone can fill me in on this one. I am comparing the run time of a perl program I wrote. Using my Mac G4 which has a 1.5 ghz processor and a 1.3 ghz PC computer (processor chip type I don't know but could find out) I am seeing that the Mac takes 14 seconds to complete what the PC does in 6! What's up with that?
Re: What up with the mac
--- Brigham Mecham [EMAIL PROTECTED] wrote: Hello Perhaps someone can fill me in on this one. I am comparing the run time of a perl program I wrote. Using my Mac G4 which has a 1.5 ghz processor and a 1.3 ghz PC computer (processor chip type I don't know but could find out) I am seeing that the Mac takes 14 seconds to complete what the PC does in 6! What's up with that? My question is where did you get a 1.5 GHz mac considering 1.25 Dual is top of the line? James __ Do you Yahoo!? Faith Hill - Exclusive Performances, Videos More http://faith.yahoo.com
Re: Why is 27 special?
Just a note: I don't know if this is related or not, but recently I had a situation where I was attempting to back up OS/X borne files to an OS/9 server. They had lengthy filenames. Every time I tried doing a 'drag-copy' I received an error -35 message. After breaking the sub-folders down finding the culprits it was indeed that the filenames were too long. Upon shortening them I was able to copy them without incident. Unfortunately I didn't count the number of characters involved. I can only assume that OS/9 has a shorter filename limit than OS/X. Oh and BTW - it is a coincidence that in your conversation: 27 is 31 minus the dot-3 extension? On Thursday, October 10, 2002, at 06:05 AM, Peter N Lewis wrote: -- From:Peter N Lewis[SMTP:[EMAIL PROTECTED]] Sent:Thursday, October 10, 2002 6:05:35 AM To: [EMAIL PROTECTED] Subject: Re: Why is 27 special? Auto forwarded by a Rule At 3:09 -0500 10/10/02, _brian_d_foy wrote: this means that the 20 fixed bytes between the volume name and the date, which are \000 in every case i looked at, is really 27 - (length of volume name). i can name partitions with names up to 27 characters, but if i go past that it look like it initially works but then gives a warning. what's the deal? what is magic about 27? why not 31? i assume that these are C strings somewhere so the null bytes makes them a nice, even number. Mac volume names are limited to 27 characters. See http://developer.apple.com/techpubs/mac/Files/Files-102.html for a description for the Master Directory Blocks (aka volume information block). If I had to guess, I'd say that the volume name was intended to be 31 characters, and then at the last minute the volume backup date field was added in at the end of the name which reduced the length of the volume name from 31 to 27 characters. Enjoy, Peter. -- I was away for two months and have just returned, and now have 4600 messages to wade through, so sorry for any delays. http://www.interarchy.com/ http://download.interarchy.com/
Re: What up with the mac
On Wednesday, October 9, 2002, at 03:31 PM, Brigham Mecham wrote: Hello Perhaps someone can fill me in on this one. I am comparing the run time of a perl program I wrote. Using my Mac G4 which has a 1.5 ghz processor and a 1.3 ghz PC computer (processor chip type I don't know but could find out) I am seeing that the Mac takes 14 seconds to complete what the PC does in 6! What's up with that? There are so many things wrong with this question that I would normally not respond to it but I think buried under the mess you wrote is a legit question. Since 1.25 Ghz is as fast as Macs are currently going I wonder if you are on 25 Mhz machine. What does the script do? Memory? HD? What else is running when you are doing this? Many questions to answer -- Lou Moran http://ellem.dyn.dhs.org:5281/resume/lmoran2002.html
Re: What up with the mac
Has anyone ran a Benchmark test on their OS X Mac? I'm a bit curious to see how Perl on OS X stacks up against other systems. I can try to run it on my iBook 366 ;) -- Bill Stephenson From: Gregory Cranz [EMAIL PROTECTED] Date: Thu, 10 Oct 2002 09:54:42 -0400 To: Brigham Mecham [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: Re: What up with the mac Comparing an arbitrary script is not necessarily a 'fair' or 'clean' test from one system to another. I would suggest working with the Benchmark module available from CPAN. This is designed to function in this capacity and is more appropriate for performance testing. As has been noted previously in responses to this query, there are a lot of things that a script might do, without divulging your script, this would probably be your best course of action. On Wednesday, October 9, 2002, at 03:31 PM, Brigham Mecham wrote: -- From: Brigham Mecham[SMTP:[EMAIL PROTECTED]] Sent: Wednesday, October 09, 2002 3:31:50 PM To: [EMAIL PROTECTED] Subject: What up with the mac Auto forwarded by a Rule Hello Perhaps someone can fill me in on this one. I am comparing the run time of a perl program I wrote. Using my Mac G4 which has a 1.5 ghz processor and a 1.3 ghz PC computer (processor chip type I don't know but could find out) I am seeing that the Mac takes 14 seconds to complete what the PC does in 6! What's up with that?
Re: What up with the mac
On Thu, 10 Oct 2002, Bill Stephenson wrote: Has anyone ran a Benchmark test on their OS X Mac? I'm a bit curious to see how Perl on OS X stacks up against other systems. Particularly interesting would be a cross comparison among, say, OSX, pure Darwin, a PPC version of Linux, and maybe PPC BSD. For comparison, these can be tried against x86 versions of the same systems. The ultimate idea being to get an idea of how OSX compares to other systems that use this hardware, and how this hardware compares to it's big brother alternative. -- Chris Devers[EMAIL PROTECTED] I had pancake makeup for brunch!
Re: What up with the mac
I didn't write to scripts below, but they are fun to play with.
Obviously some adjustment would be needed to compare across systems.
#
#!/usr/bin/perl Benchmark_demo1
#Measure CPU usage of a some portion of a program
use Benchmark;
# generate list of all text files in /etc
text_files = grep { -f and -T } glob('/etc/*');
timethis(100, 'sort_by_size(text_files)');
# sort the files names according to file sizes
sub sort_by_size {
my files = _;
files = sort { -s $a = -s $b } files;
return files;
}
#
#
#!/usr/bin/perl Benchmark_demo2
#Can confirm that one technique is faster than another
use Benchmark;
# generate list of all text files in /etc
text_files = grep { -f and -T } glob('/etc/*');
timethis(100, 'faster_sort_by_size(text_files)');
# sort the files names according to file sizes,
# stat'ing each file just once
sub faster_sort_by_size {
my files = _;
files = map { $_-[1] }
sort { $a-[0] = $b-[0] }
map { [ -s $_, $_ ] } files;
return files;
}
#
gd croaking
Folks, I haven't messed with the OS at all. Perl 5.6.0 that comes with OS X 10.2. I built gd 1.8.4 using Scott Anguish's directions on stepwise (as I have done before), and that worked just as expected. Then I built a specific perl module that helps makes maps (used to work fine on 10.1.whatever. I run my scripts unchanged, and I get the following in the apache error_log. Seems like gd is not happy. Without any further info to share (I really don't know what else to offer), can anyone shed some light on the following, or guide me to someplace I can find answers? Many thanks. Puneet. % tail -f /var/log/httpd/error_log dyld: perl Undefined symbols: _gdFontGiant _gdFontLarge _gdFontMediumBold _gdFontSmall _gdFontTiny _gdImageArc _gdImageColorAllocate _gdImageColorTransparent _gdImageCopy _gdImageCopyMerge _gdImageCopyResized _gdImageCreate _gdImageCreateFromJpeg _gdImageCreateFromPng _gdImageDestroy _gdImageFillToBorder _gdImageFilledPolygon _gdImageFilledRectangle _gdImageInterlace _gdImageJpeg _gdImageJpegPtr _gdImageLine _gdImagePng _gdImagePngPtr _gdImagePolygon _gdImageRectangle _gdImageSetBrush _gdImageSetPixel _gdImageSetStyle _gdImageSetTile _gdImageString _gdImageStringFT _gdImageWBMP _gdImageWBMPPtr [Thu Oct 10 11:00:46 2002] [error] [client 127.0.0.1] Premature end of script headers: /Users/pkishor/Sites/bims/index.pl
Re: Installation of LWP fails
On Wednesday, October 9, 2002, at 11:38 PM, Adam Fishman wrote: (You get this message, because MakeMaker could not find /System/Library/Perl/darwin/CORE/perl.h) Well, do you have this file? David -- David Wheeler AIM: dwTheory [EMAIL PROTECTED] ICQ: 15726394 http://david.wheeler.net/ Yahoo!: dew7e Jabber: [EMAIL PROTECTED]
Re: Installation of LWP fails
I have exactly the same problem on a machine at work running Mac OS X Server 10.2. Don't know how to fix it. Would like to be able to run the LWP module too. PowerPalle On torsdag, okt 10, 2002, at 19:17 Europe/Copenhagen, David Wheeler wrote: On Wednesday, October 9, 2002, at 11:38 PM, Adam Fishman wrote: (You get this message, because MakeMaker could not find /System/Library/Perl/darwin/CORE/perl.h) Well, do you have this file? David -- David Wheeler AIM: dwTheory [EMAIL PROTECTED] ICQ: 15726394 http://david.wheeler.net/ Yahoo!: dew7e Jabber: [EMAIL PROTECTED]
Re: Adding path to @INC for use with web server
From: Adam Witney [EMAIL PROTECTED] Date: Thu, 10 Oct 2002 11:09:38 +0100 To: MacOS X perl [EMAIL PROTECTED] Subject: Adding path to @INC for use with web server Hi, Searching the archives I have been able to find out how to get Perl to search other paths for modules when invoked from the terminal or from GUI apps such as BBEdit, however I cannot get them recognised by cgi scripts. I read somewhere to add this line to httpd.conf You can include this code in httpd.conf: Perl use lib ''; /Perl I assume that this directive requires mod_perl Alternatively you can do PerlRequire /../../perl_config_file.pl and then in that perl config file, include your 'use lib' code.
Re: gd croaking
Ok, here's some more info that I was able to put together. I built gd and supporting libraries using gcc 3.1. To build another program (that actually eventually generates a perl module), I had to revert to gcc 2.x. I, then, reverted back to gcc 3.x and built the perl specific module. Running my perl scripts hence produces the errors below. The dyld: perl Undefined symbols: portion indicates there might be some binary incompatibility. Between what and what though? Is there a way I can test this? (I guess, in a manner of speaking, I did test it and learned it is incompatible :-( ) Puneet Kishor wrote: Folks, I haven't messed with the OS at all. I am using the Perl 5.6.0 that comes with OS X 10.2. I built gd 1.8.4 using Scott Anguish's directions on stepwise (as I have done before), and that worked just as expected. Then I built a specific perl module that helps makes maps (used to work fine on 10.1.whatever. I run my scripts unchanged, and I get the following in the apache error_log. Seems like gd is not happy. Without any further info to share (I really don't know what else to offer), can anyone shed some light on the following, or guide me to someplace I can find answers? Many thanks. Puneet. % tail -f /var/log/httpd/error_log dyld: perl Undefined symbols: _gdFontGiant _gdFontLarge _gdFontMediumBold _gdFontSmall _gdFontTiny _gdImageArc _gdImageColorAllocate _gdImageColorTransparent _gdImageCopy _gdImageCopyMerge _gdImageCopyResized _gdImageCreate _gdImageCreateFromJpeg _gdImageCreateFromPng _gdImageDestroy _gdImageFillToBorder _gdImageFilledPolygon _gdImageFilledRectangle _gdImageInterlace _gdImageJpeg _gdImageJpegPtr _gdImageLine _gdImagePng _gdImagePngPtr _gdImagePolygon _gdImageRectangle _gdImageSetBrush _gdImageSetPixel _gdImageSetStyle _gdImageSetTile _gdImageString _gdImageStringFT _gdImageWBMP _gdImageWBMPPtr [Thu Oct 10 11:00:46 2002] [error] [client 127.0.0.1] Premature end of script headers: /Users/pkishor/Sites/bims/index.pl
Jaguar Perl 5.6.0 dyld error
Hoping someone has seen this. I've read all about the dyld: perl Undefined symbol: errors when upgrading to 5.8.0, but I'm running into these errors while still running 5.6.0 on certain modules. Specifically, I'm trying to use Jeff Horwitz's Authen::Krb5 and get the following output: dyld: perl Undefined symbols: _krb5_free_address _krb5_free_enc_tkt_part _krb5_free_krbhst _krb5_gen_portaddr _krb5_gen_replay_name _krb5_get_krbhst _krb5_init_ets Trace/BPT trap During the Authen::Krb5 compile i get some warnings: Krb5.xs:317: warning: passing arg 2 of `Perl_sv_2pv' from incompatible pointer type Krb5.xs: In function `XS_Authen__Krb5_rd_req': etc... but it seems to build ok. Anyone have an idea on this one? Thanks, Kelly
Re: gd croaking
Puneet, Think I had same issues, and gave up and used gnuplot instead for some graph creation, as it does put out graphs like the ones I use on my site well (http://www.dkgomez.com/cgi-bin/housetemp.pl). Think I used fink to do the install of gnuplot Dave Gomez On 10/10/02 2:27 PM, Puneet Kishor [EMAIL PROTECTED] wrote: Ok, here's some more info that I was able to put together. I built gd and supporting libraries using gcc 3.1. To build another program (that actually eventually generates a perl module), I had to revert to gcc 2.x. I, then, reverted back to gcc 3.x and built the perl specific module. Running my perl scripts hence produces the errors below. The dyld: perl Undefined symbols: portion indicates there might be some binary incompatibility. Between what and what though? Is there a way I can test this? (I guess, in a manner of speaking, I did test it and learned it is incompatible :-( ) Puneet Kishor wrote: Folks, I haven't messed with the OS at all. I am using the Perl 5.6.0 that comes with OS X 10.2. I built gd 1.8.4 using Scott Anguish's directions on stepwise (as I have done before), and that worked just as expected. Then I built a specific perl module that helps makes maps (used to work fine on 10.1.whatever. I run my scripts unchanged, and I get the following in the apache error_log. Seems like gd is not happy. Without any further info to share (I really don't know what else to offer), can anyone shed some light on the following, or guide me to someplace I can find answers? Many thanks. Puneet. % tail -f /var/log/httpd/error_log dyld: perl Undefined symbols: _gdFontGiant _gdFontLarge _gdFontMediumBold _gdFontSmall _gdFontTiny _gdImageArc _gdImageColorAllocate _gdImageColorTransparent _gdImageCopy _gdImageCopyMerge _gdImageCopyResized _gdImageCreate _gdImageCreateFromJpeg _gdImageCreateFromPng _gdImageDestroy _gdImageFillToBorder _gdImageFilledPolygon _gdImageFilledRectangle _gdImageInterlace _gdImageJpeg _gdImageJpegPtr _gdImageLine _gdImagePng _gdImagePngPtr _gdImagePolygon _gdImageRectangle _gdImageSetBrush _gdImageSetPixel _gdImageSetStyle _gdImageSetTile _gdImageString _gdImageStringFT _gdImageWBMP _gdImageWBMPPtr [Thu Oct 10 11:00:46 2002] [error] [client 127.0.0.1] Premature end of script headers: /Users/pkishor/Sites/bims/index.pl
OT Java pseudo-benchmark (was Re: What up with the mac)
Okay, here's the Java program I was talking about, since someone might
want it and I'm going to be off-list for a while:
-begin code
/**
* Let's try the Factorial in BigInteger
*
* @author Joel Rees, Altech Corporation, Esaka, Japan
* Copyright September 2002
* May be copied, modified, and/or used freely.
* No warranty. Use at your own risk.
*
* @version 0.1
*/
import java.lang.Class;
import java.math.BigInteger;
public class BigFactorial
{
public static void main( String[] args )
{ if ( ( args.length 1 ) || ( args[ 0 ].charAt( 0 ) == '-' ) )
{ System.out.println( Usage:
/* Okay, this is ridiculous. */
+ BigFactorial.class.getName()
+ integer {, integer } );
}
else
{ for ( int i = 0; i args.length; ++i )
{ BigInteger input = new BigInteger( args[ i ] );
System.out.println(
(
+ input.toString()
+ )! == + factorial( input ).toString() );
}
}
}
/* Let's not try to blow the stack with the old
* forced example of recursion, at any rate.
*/
public static BigInteger factorial( BigInteger n )
{ if ( n.compareTo( BigInteger.ZERO ) 0 )
{ return new BigInteger( 0 );
}
BigInteger result = new BigInteger( 1 );
while ( n.compareTo( BigInteger.ONE ) 0 )
{ result = result.multiply( n );
n = n.subtract( BigInteger.ONE );
}
return result;
}
}
--end code-
Should be easy to re-write in Perl.
--
Joel Rees [EMAIL PROTECTED]
