[29785] in Perl-Users-Digest
Perl-Users Digest, Issue: 1028 Volume: 11
daemon@ATHENA.MIT.EDU (Perl-Users Digest)
Tue Nov 13 06:10:13 2007
Date: Tue, 13 Nov 2007 03:09:05 -0800 (PST)
From: Perl-Users Digest <Perl-Users-Request@ruby.OCE.ORST.EDU>
To: Perl-Users@ruby.OCE.ORST.EDU (Perl-Users Digest)
Perl-Users Digest Tue, 13 Nov 2007 Volume: 11 Number: 1028
Today's topics:
Concept of God in Islam <jipksaman@gmail.com>
fastcgi vs mod perl vs apache vs lighttpd vs perlbal <gavcomedy@gmail.com>
peculiar behaviour with prototyped routines <christian.hansel@cpi-service.com>
peculiar behaviour with prototyped routines <christian.hansel@cpi-service.com>
Posting Guidelines for comp.lang.perl.misc ($Revision: tadmc@seesig.invalid
Re: Reg- Floating point variables <nithyananthamm@yahoo.com>
Re: Reg- Floating point variables <nithyananthamm@yahoo.com>
Re: Reg- Floating point variables <nithyananthamm@yahoo.com>
Re: Reg- Floating point variables <nithyananthamm@yahoo.com>
replace string contaning \n cieux87-fin@yahoo.com
Re: replace string contaning \n sheinrich@my-deja.com
Re: sleep/fork/shell/SIGCHLD interaction problem <ced@blv-sam-01.ca.boeing.com>
Digest Administrivia (Last modified: 6 Apr 01) (Perl-Users-Digest Admin)
----------------------------------------------------------------------
Date: Mon, 12 Nov 2007 23:25:39 -0800
From: abdo911 <jipksaman@gmail.com>
Subject: Concept of God in Islam
Message-Id: <1194938739.021380.261500@v3g2000hsg.googlegroups.com>
WAMY Series: On Islam No.9.Introduction
God's Attributes
The Oneness of God
The Believer's Attitude
Introduction
It is a known fact that every language has one or more terms that are
used in reference to God and sometimes to lesser deities. This is not
the case with Allah. Allah is the personal name of the One true God.
Nothing else can be called Allah. The term has no plural or gender.
This shows its uniqueness when compared with the word "god," which can
be made plural, as in "gods," or made feminine, as in "goddess." It is
interesting to notice that Allah is the personal name of God in
Aramaic, the language of Jesus and a sister language of Arabic.The One
true God is a reflection of the unique concept that Islam associates
with God. To a Muslim, Allah is the Almighty Creator and Sustainer of
the universe, Who is similar to nothing, and nothing is comparable to
Him. The Prophet Muhammad was asked by his contemporaries about Allah;
the answer came directly from God Himself in the form of a short
chapter of the Qur'an, which is considered to be the essence of the
unity or the motto of monotheism. This is chapter 112, which reads:"
In the name of Allah, the Merciful, the Compassionate. Say (O
Muhammad), He is God, the One God, the Everlasting Refuge, who has not
begotten, nor has been begotten, and equal to Him is not anyone".Some
non-Muslims allege that God in Islam is a stern and cruel God who
demands to be obeyed fully and is not loving and kind. Nothing could
be farther from the truth than this allegation. It is enough to know
that, with the exception of one, each of the 114 chapters of the
Qur'an begins with the verse " In the name of God, the Merciful, the
Compassionate". In one of the sayings of Prophet Muhammad (PBUH), we
are told that " God is more loving and kind than a mother to her dear
child".On the other hand, God is also Just. Hence, evildoers and
sinners must have their share of punishment, and the virtuous must
have God's bounties and favors. Actually, God's attribute of Mercy has
full manifestation in His attribute of Justice. People suffering
throughout their lives for His sake should not receive similar
treatment from their Lord as people who oppress and exploit others
their whole lives. Expecting similar treatment for them would amount
to negating the very belief in the accountability of man in the
Hereafter and thereby negate all the incentives for a moral and
virtuous life in this world. The following Qur'anic verses are very
clear and straightforward in this respect.
Verily, for the Righteous are gardens of Delight, in the Presence of
their Lord. Shall We then treat the people of Faith like the people of
Sin? What is the matter with you? How judge you?
Islam rejects characterizing God in any human form or depicting Him as
favoring certain individuals or nations on the basis of wealth, power
or race. He created the human-beings as equals. They may distinguish
themselves and get His favor through virtue and piety only.
The concepts that God rested on the seventh day of creation, that God
wrestled with one of His soldiers, that God is an envious plotter
against mankind, and that God is incarnate in any human being are
considered blasphemy from the Islamic point of view.
The unique usage of Allah as a personal name of God is a reflection of
Islam's emphasis on the purity of the belief in God that is the
essence of the message of all God's messengers. Because of this, Islam
considers associating any deity or personality with God as a deadly
sin that God will never forgive, despite the fact that He may forgive
all other sins.
The Creator must be of a different nature from the things created
because if He is of the same nature as they are, He will be temporal
and will therefore need a maker. It follows that nothing is like Him.
If the maker is not temporal, then he must be eternal. But if he is
eternal, he cannot be caused, and if nothing caused Him to come into
existence, nothing outside Him causes Him to continue to exist, which
means that he must be self-sufficient. And if He does not depend on
anything for the continuance of His own existence, then this existence
can have no end. The Creator is therefore eternal and everlasting: "He
is the First and the Last".
He is Self-sufficient or Self-subsistent, or, to use a Qur'anic term,
Al-Qayyum The Creator does not create only in the sense of bringing
things into being, He. also preserves them and takes them out of
existence and is the ultimate cause of whatever happens to them.
" God is the Creator of everything. He is the guardian over
everything. Unto Him belong the keys of the heavens and the
earth" (39:62-63).
" No creature is there crawling on the earth, but its provision rests
on God. He knows its lodging place and its repository" (11:16).
God's Attributes
If the Creator is Eternal and Everlasting, then His attributes must
also be eternal and everlasting. He should not lose any of His
attributes nor acquire new ones. If this is so, then his attributes
are absolute. Can there be more than one Creator with such absolute
attributes? Can there be, for example, two absolutely powerful
Creators? A moment's thought shows that this is not feasible.
The Qur'an summarizes this argument in the following verses:" God has
not taken to Himself any son, nor is there any god with Him: for then
each god would have taken of that which he created and some of them
would have risen up over others" (23:91).
" And why, were there gods in earth and heaven other than God, they
(heaven and earth) would surely go to ruin" (21:22).
The Oneness of God
The Qur'an reminds us of the falsity of all alleged gods. To the
worshippers of man-made objects it asks:" Do you worship what you have
carved yourself" (37:95). " Or have you taken unto yourself others
beside Him to be your protectors, even such as have no power either
for good or for harm to themselves" (13:16).
To the worshippers of heavenly bodies it cites the story of Abraham:"
When night outspread over him, he saw a star and said: This is my
Lord. But when it set, he said: I love not the setters. When he saw
the moon rising, he said: This is my Lord. But when it set, he said:
If my Lord does not guide me, I shall surely be of the people gone
astray. When he saw the sun rising, he said: This is my Lord; this is
greater. But when it set, he said: O my people, surely I quit that
which you associate, I have turned my face to Him who originated the
heavens and the earth; a man of pure faith, I am not one of the
idolators" (6:76-79).
The Believer's Attitude
In order to be a Muslim, that is, to surrender oneself to God, it is
necessary to believe in the oneness of God, in the sense of His being
the only Creator, Preserver, Nourisher, etc. But this belief, later
called Tawhid Ar-Rububiyyah, is not enough. Many of the idolators knew
and believed that only the Supreme God could do all this. But this was
not enough to make them Muslims. To tawhid ar-rububiyyah, one must add
tawhid al-'uluhiyyah. That is, one acknowledges the fact that it is
God alone who deserves to be worshipped, and thus abstains from
worshipping any other thing or being.
Having achieved this knowledge of the one true God, man should
constantly have faith in Him, and should allow nothing to induce him
to deny truth.
When faith enters a person's heart, it causes certain mental states
that result in certain actions. Taken together, these mental states
and actions are the proof for the true faith. The Prophet said:" Faith
is that which resides firmly in the heart and which is proved by
deeds".
Foremost among those mental stated is the feeling of gratitude towards
God, which could be said to be the essence of ibada (worship).
The feeling of gratitude is so important that a non-believer is called
'kafir', which means 'one who denies a truth' and also 'one who is
ungrateful'.
A believer loves, and is grateful to God for the bounties He bestowed
upon him, but being aware of the fact that his good deeds, whether
mental or physical, are far from being commensurate with Divine
favors, he is always anxious lest God should punish him, here or in
the Hereafter. He, therefore, fears Him, surrenders himself to Him and
serves Him with great humility. One cannot be in such a mental state
without being almost all the time mindful of God. Remembering God is
thus the life force of faith, without which it fades and withers
away.
The Qur'an tries to promote this feeling of gratitude by repeating the
attributes of God very frequently. We find most of these attributes
mentioned together in the following verses of the Qur'an:" He is God;
there is no god but He. He is the Knower of the unseen and the
visible; He is the All-Merciful, the All-Compassionate. He is God;
there is no god but He. He is the King, the All-Holy, the All-Peace,
the Guardian of the Faith, the All-Preserver, the All-Mighty, the All-
Compeller, the All-Sublime. Glory be to God, above that they
associate! He is God, the Creator, the Maker, the Shaper. To Him
belong the Names Most Beautiful. All that is in the heavens and the
earth magnifies Him; He is the Almighty, the All-Wise" (59:22-24).
" There is no god but He, the Living, the Everlasting. Slumber seizes
Him not, nor sleep. To Him belongs all that is in the heavens and the
earth. Who is there that shall intercede with Him save by His leave?
He knows what lies before them, and what is after them, and they
comprehend not anything of His knowledge save such as He wills. His
throne comprises the heavens and earth. The preserving of them
oppresses Him not; He is the All-High, the All-Glorious" (2:255).
People of the Book, go not beyond the bounds in your religion, and say
not as to God but the truth.
" The Messiah, Jesus, son of Mary, was only the Messenger of God, and
His Word that He committed to Mary, and a Spirit from Him. So believe
in God and His Messengers, and say not "Three". Refrain; better it is
for you. God is only one God. Glory be to Him - (He is) above having a
son" (4:171).
------------------------------
Date: Mon, 12 Nov 2007 23:57:20 -0800
From: gavino <gavcomedy@gmail.com>
Subject: fastcgi vs mod perl vs apache vs lighttpd vs perlbal
Message-Id: <1194940640.191688.92440@i38g2000prf.googlegroups.com>
what is fastest combo folks?
------------------------------
Date: Tue, 13 Nov 2007 00:49:37 -0800
From: "cvh@LE" <christian.hansel@cpi-service.com>
Subject: peculiar behaviour with prototyped routines
Message-Id: <1194943777.446858.67920@57g2000hsv.googlegroups.com>
Hi all,
Experimenting with prototyping I came across a rather peculiar and
inexplicable behaviour of routines depending on whether they are
defined in
the main file or a required library.
The following file :
#testlib.pl
#! /usr/bin/perl
sub test1(\@$) {
my @a=@{(shift)};
my $v=shift;
print "\n----------\nTest1:\n array: @a\n v:$v\n";
}
sub test2(\@$) {
my @a=@_;
my $v=pop @a;
print "\n----------\nTest2:\n array: @a\n v:$v\n";
}
print "\nin libfile..\n";
my @t1=(0,1,2,3,4,5,6,7,8,9);
test1(@t1,100);
test2(@t1,100);
1;
prints when called directly
>bash3.1 cvh@shogun::~$ perl testlib.pl
in libfile..
----------
Test1:
array: 0 1 2 3 4 5 6 7 8 9
v:100
----------
Test2:
array: ARRAY(0x804cf9c)
v:100
>bash3.1 cvh@shogun::~$
However when this file is included/required in another file the
functions
behave totally different, depending on whether the routine is called
from
where it is defined or from a higher hierarchy.
I doubt that this is intended:
The file testfile.pl
#! /usr/bin/perl
require "./testlib.pl";
print "\nin mainfile..\n";
my @t1=(0,1,2,3,4,5,6,7,8,9);
test1(@t1,100);
test2(@t1,100);
shows a reverse behaviour than that from before
bash3.1 cvh@shogun::~$ perl testfile.pl
in libfile..
----------
Test1:
array: 0 1 2 3 4 5 6 7 8 9
v:100
----------
Test2:
array: ARRAY(0x8060970)
v:100
in mainfile..
----------
Test1:
array:
v:1
----------
Test2:
array: 0 1 2 3 4 5 6 7 8 9
v:100
bash3.1 cvh@shogun::~$
As can be seen while the test1-routine does not correctly take the
provided
array parameter and instead hands @t1's first element to the second
parameter this time the second routine test2 behaves the same way
test1 did
when called from inside testlib.pl.
Can someone explain this rather peculiar behaviour or point me towards
my
mistake?. Or is this simply a bug in perl's prototyping?
Any hint or answer is greatly appreciated
CVH
------------------------------
Date: Tue, 13 Nov 2007 00:49:41 -0800
From: "cvh@LE" <christian.hansel@cpi-service.com>
Subject: peculiar behaviour with prototyped routines
Message-Id: <1194943781.700898.204690@k79g2000hse.googlegroups.com>
Hi all,
Experimenting with prototyping I came across a rather peculiar and
inexplicable behaviour of routines depending on whether they are
defined in
the main file or a required library.
The following file :
#testlib.pl
#! /usr/bin/perl
sub test1(\@$) {
my @a=@{(shift)};
my $v=shift;
print "\n----------\nTest1:\n array: @a\n v:$v\n";
}
sub test2(\@$) {
my @a=@_;
my $v=pop @a;
print "\n----------\nTest2:\n array: @a\n v:$v\n";
}
print "\nin libfile..\n";
my @t1=(0,1,2,3,4,5,6,7,8,9);
test1(@t1,100);
test2(@t1,100);
1;
prints when called directly
>bash3.1 cvh@shogun::~$ perl testlib.pl
in libfile..
----------
Test1:
array: 0 1 2 3 4 5 6 7 8 9
v:100
----------
Test2:
array: ARRAY(0x804cf9c)
v:100
>bash3.1 cvh@shogun::~$
However when this file is included/required in another file the
functions
behave totally different, depending on whether the routine is called
from
where it is defined or from a higher hierarchy.
I doubt that this is intended:
The file testfile.pl
#! /usr/bin/perl
require "./testlib.pl";
print "\nin mainfile..\n";
my @t1=(0,1,2,3,4,5,6,7,8,9);
test1(@t1,100);
test2(@t1,100);
shows a reverse behaviour than that from before
bash3.1 cvh@shogun::~$ perl testfile.pl
in libfile..
----------
Test1:
array: 0 1 2 3 4 5 6 7 8 9
v:100
----------
Test2:
array: ARRAY(0x8060970)
v:100
in mainfile..
----------
Test1:
array:
v:1
----------
Test2:
array: 0 1 2 3 4 5 6 7 8 9
v:100
bash3.1 cvh@shogun::~$
As can be seen while the test1-routine does not correctly take the
provided
array parameter and instead hands @t1's first element to the second
parameter this time the second routine test2 behaves the same way
test1 did
when called from inside testlib.pl.
Can someone explain this rather peculiar behaviour or point me towards
my
mistake?. Or is this simply a bug in perl's prototyping?
Any hint or answer is greatly appreciated
CVH
------------------------------
Date: Tue, 13 Nov 2007 08:10:37 GMT
From: tadmc@seesig.invalid
Subject: Posting Guidelines for comp.lang.perl.misc ($Revision: 1.8 $)
Message-Id: <1_c_i.20591$Pv2.1089@newssvr23.news.prodigy.net>
Outline
Before posting to comp.lang.perl.misc
Must
- Check the Perl Frequently Asked Questions (FAQ)
- Check the other standard Perl docs (*.pod)
Really Really Should
- Lurk for a while before posting
- Search a Usenet archive
If You Like
- Check Other Resources
Posting to comp.lang.perl.misc
Is there a better place to ask your question?
- Question should be about Perl, not about the application area
How to participate (post) in the clpmisc community
- Carefully choose the contents of your Subject header
- Use an effective followup style
- Speak Perl rather than English, when possible
- Ask perl to help you
- Do not re-type Perl code
- Provide enough information
- Do not provide too much information
- Do not post binaries, HTML, or MIME
Social faux pas to avoid
- Asking a Frequently Asked Question
- Asking a question easily answered by a cursory doc search
- Asking for emailed answers
- Beware of saying "doesn't work"
- Sending a "stealth" Cc copy
Be extra cautious when you get upset
- Count to ten before composing a followup when you are upset
- Count to ten after composing and before posting when you are upset
-----------------------------------------------------------------
Posting Guidelines for comp.lang.perl.misc ($Revision: 1.8 $)
This newsgroup, commonly called clpmisc, is a technical newsgroup
intended to be used for discussion of Perl related issues (except job
postings), whether it be comments or questions.
As you would expect, clpmisc discussions are usually very technical in
nature and there are conventions for conduct in technical newsgroups
going somewhat beyond those in non-technical newsgroups.
The article at:
http://www.catb.org/~esr/faqs/smart-questions.html
describes how to get answers from technical people in general.
This article describes things that you should, and should not, do to
increase your chances of getting an answer to your Perl question. It is
available in POD, HTML and plain text formats at:
http://www.rehabitation.com/clpmisc.shtml
For more information about netiquette in general, see the "Netiquette
Guidelines" at:
http://andrew2.andrew.cmu.edu/rfc/rfc1855.html
A note to newsgroup "regulars":
Do not use these guidelines as a "license to flame" or other
meanness. It is possible that a poster is unaware of things
discussed here. Give them the benefit of the doubt, and just
help them learn how to post, rather than assume that they do
know and are being the "bad kind" of Lazy.
A note about technical terms used here:
In this document, we use words like "must" and "should" as
they're used in technical conversation (such as you will
encounter in this newsgroup). When we say that you *must* do
something, we mean that if you don't do that something, then
it's unlikely that you will benefit much from this group.
We're not bossing you around; we're making the point without
lots of words.
Do *NOT* send email to the maintainer of these guidelines. It will be
discarded unread. The guidelines belong to the newsgroup so all
discussion should appear in the newsgroup. I am just the secretary that
writes down the consensus of the group.
Before posting to comp.lang.perl.misc
Must
This section describes things that you *must* do before posting to
clpmisc, in order to maximize your chances of getting meaningful replies
to your inquiry and to avoid getting flamed for being lazy and trying to
have others do your work.
The perl distribution includes documentation that is copied to your hard
drive when you install perl. Also installed is a program for looking
things up in that (and other) documentation named 'perldoc'.
You should either find out where the docs got installed on your system,
or use perldoc to find them for you. Type "perldoc perldoc" to learn how
to use perldoc itself. Type "perldoc perl" to start reading Perl's
standard documentation.
Check the Perl Frequently Asked Questions (FAQ)
Checking the FAQ before posting is required in Big 8 newsgroups in
general, there is nothing clpmisc-specific about this requirement.
You are expected to do this in nearly all newsgroups.
You can use the "-q" switch with perldoc to do a word search of the
questions in the Perl FAQs.
Check the other standard Perl docs (*.pod)
The perl distribution comes with much more documentation than is
available for most other newsgroups, so in clpmisc you should also
see if you can find an answer in the other (non-FAQ) standard docs
before posting.
It is *not* required, or even expected, that you actually *read* all of
Perl's standard docs, only that you spend a few minutes searching them
before posting.
Try doing a word-search in the standard docs for some words/phrases
taken from your problem statement or from your very carefully worded
"Subject:" header.
Really Really Should
This section describes things that you *really should* do before posting
to clpmisc.
Lurk for a while before posting
This is very important and expected in all newsgroups. Lurking means
to monitor a newsgroup for a period to become familiar with local
customs. Each newsgroup has specific customs and rituals. Knowing
these before you participate will help avoid embarrassing social
situations. Consider yourself to be a foreigner at first!
Search a Usenet archive
There are tens of thousands of Perl programmers. It is very likely
that your question has already been asked (and answered). See if you
can find where it has already been answered.
One such searchable archive is:
http://groups.google.com/advanced_group_search
If You Like
This section describes things that you *can* do before posting to
clpmisc.
Check Other Resources
You may want to check in books or on web sites to see if you can
find the answer to your question.
But you need to consider the source of such information: there are a
lot of very poor Perl books and web sites, and several good ones
too, of course.
Posting to comp.lang.perl.misc
There can be 200 messages in clpmisc in a single day. Nobody is going to
read every article. They must decide somehow which articles they are
going to read, and which they will skip.
Your post is in competition with 199 other posts. You need to "win"
before a person who can help you will even read your question.
These sections describe how you can help keep your article from being
one of the "skipped" ones.
Is there a better place to ask your question?
Question should be about Perl, not about the application area
It can be difficult to separate out where your problem really is,
but you should make a conscious effort to post to the most
applicable newsgroup. That is, after all, where you are the most
likely to find the people who know how to answer your question.
Being able to "partition" a problem is an essential skill for
effectively troubleshooting programming problems. If you don't get
that right, you end up looking for answers in the wrong places.
It should be understood that you may not know that the root of your
problem is not Perl-related (the two most frequent ones are CGI and
Operating System related), so off-topic postings will happen from
time to time. Be gracious when someone helps you find a better place
to ask your question by pointing you to a more applicable newsgroup.
How to participate (post) in the clpmisc community
Carefully choose the contents of your Subject header
You have 40 precious characters of Subject to win out and be one of
the posts that gets read. Don't waste them. Take care while
composing them, they are the key that opens the door to getting an
answer.
Spend them indicating what aspect of Perl others will find if they
should decide to read your article.
Do not spend them indicating "experience level" (guru, newbie...).
Do not spend them pleading (please read, urgent, help!...).
Do not spend them on non-Subjects (Perl question, one-word
Subject...)
For more information on choosing a Subject see "Choosing Good
Subject Lines":
http://www.cpan.org/authors/id/D/DM/DMR/subjects.post
Part of the beauty of newsgroup dynamics, is that you can contribute
to the community with your very first post! If your choice of
Subject leads a fellow Perler to find the thread you are starting,
then even asking a question helps us all.
Use an effective followup style
When composing a followup, quote only enough text to establish the
context for the comments that you will add. Always indicate who
wrote the quoted material. Never quote an entire article. Never
quote a .signature (unless that is what you are commenting on).
Intersperse your comments *following* each section of quoted text to
which they relate. Unappreciated followup styles are referred to as
"top-posting", "Jeopardy" (because the answer comes before the
question), or "TOFU" (Text Over, Fullquote Under).
Reversing the chronology of the dialog makes it much harder to
understand (some folks won't even read it if written in that style).
For more information on quoting style, see:
http://web.presby.edu/~nnqadmin/nnq/nquote.html
Speak Perl rather than English, when possible
Perl is much more precise than natural language. Saying it in Perl
instead will avoid misunderstanding your question or problem.
Do not say: I have variable with "foo\tbar" in it.
Instead say: I have $var = "foo\tbar", or I have $var = 'foo\tbar',
or I have $var = <DATA> (and show the data line).
Ask perl to help you
You can ask perl itself to help you find common programming mistakes
by doing two things: enable warnings (perldoc warnings) and enable
"strict"ures (perldoc strict).
You should not bother the hundreds/thousands of readers of the
newsgroup without first seeing if a machine can help you find your
problem. It is demeaning to be asked to do the work of a machine. It
will annoy the readers of your article.
You can look up any of the messages that perl might issue to find
out what the message means and how to resolve the potential mistake
(perldoc perldiag). If you would like perl to look them up for you,
you can put "use diagnostics;" near the top of your program.
Do not re-type Perl code
Use copy/paste or your editor's "import" function rather than
attempting to type in your code. If you make a typo you will get
followups about your typos instead of about the question you are
trying to get answered.
Provide enough information
If you do the things in this item, you will have an Extremely Good
chance of getting people to try and help you with your problem!
These features are a really big bonus toward your question winning
out over all of the other posts that you are competing with.
First make a short (less than 20-30 lines) and *complete* program
that illustrates the problem you are having. People should be able
to run your program by copy/pasting the code from your article. (You
will find that doing this step very often reveals your problem
directly. Leading to an answer much more quickly and reliably than
posting to Usenet.)
Describe *precisely* the input to your program. Also provide example
input data for your program. If you need to show file input, use the
__DATA__ token (perldata.pod) to provide the file contents inside of
your Perl program.
Show the output (including the verbatim text of any messages) of
your program.
Describe how you want the output to be different from what you are
getting.
If you have no idea at all of how to code up your situation, be sure
to at least describe the 2 things that you *do* know: input and
desired output.
Do not provide too much information
Do not just post your entire program for debugging. Most especially
do not post someone *else's* entire program.
Do not post binaries, HTML, or MIME
clpmisc is a text only newsgroup. If you have images or binaries
that explain your question, put them in a publically accessible
place (like a Web server) and provide a pointer to that location. If
you include code, cut and paste it directly in the message body.
Don't attach anything to the message. Don't post vcards or HTML.
Many people (and even some Usenet servers) will automatically filter
out such messages. Many people will not be able to easily read your
post. Plain text is something everyone can read.
Social faux pas to avoid
The first two below are symptoms of lots of FAQ asking here in clpmisc.
It happens so often that folks will assume that it is happening yet
again. If you have looked but not found, or found but didn't understand
the docs, say so in your article.
Asking a Frequently Asked Question
It should be understood that you may have missed the applicable FAQ
when you checked, which is not a big deal. But if the Frequently
Asked Question is worded similar to your question, folks will assume
that you did not look at all. Don't become indignant at pointers to
the FAQ, particularly if it solves your problem.
Asking a question easily answered by a cursory doc search
If folks think you have not even tried the obvious step of reading
the docs applicable to your problem, they are likely to become
annoyed.
If you are flamed for not checking when you *did* check, then just
shrug it off (and take the answer that you got).
Asking for emailed answers
Emailed answers benefit one person. Posted answers benefit the
entire community. If folks can take the time to answer your
question, then you can take the time to go get the answer in the
same place where you asked the question.
It is OK to ask for a *copy* of the answer to be emailed, but many
will ignore such requests anyway. If you munge your address, you
should never expect (or ask) to get email in response to a Usenet
post.
Ask the question here, get the answer here (maybe).
Beware of saying "doesn't work"
This is a "red flag" phrase. If you find yourself writing that,
pause and see if you can't describe what is not working without
saying "doesn't work". That is, describe how it is not what you
want.
Sending a "stealth" Cc copy
A "stealth Cc" is when you both email and post a reply without
indicating *in the body* that you are doing so.
Be extra cautious when you get upset
Count to ten before composing a followup when you are upset
This is recommended in all Usenet newsgroups. Here in clpmisc, most
flaming sub-threads are not about any feature of Perl at all! They
are most often for what was seen as a breach of netiquette. If you
have lurked for a bit, then you will know what is expected and won't
make such posts in the first place.
But if you get upset, wait a while before writing your followup. I
recommend waiting at least 30 minutes.
Count to ten after composing and before posting when you are upset
After you have written your followup, wait *another* 30 minutes
before committing yourself by posting it. You cannot take it back
once it has been said.
AUTHOR
Tad McClellan and many others on the comp.lang.perl.misc newsgroup.
--
Tad McClellan
email: perl -le "print scalar reverse qq/moc.noitatibaher\100cmdat/"
------------------------------
Date: Mon, 12 Nov 2007 21:18:08 -0800
From: Nithy <nithyananthamm@yahoo.com>
Subject: Re: Reg- Floating point variables
Message-Id: <1194931088.182195.104210@v29g2000prd.googlegroups.com>
On Nov 12, 9:39 pm, Sherman Pendley <spamt...@dot-app.org> wrote:
> Nithy <nithyananth...@yahoo.com> writes:
> > If I run this code, it doesn't terminate when $count reach 0.9. Its
> > keep on increasing. And after 5.9 its showing 5.99999999999999 & so
> > on..
> > But If I limits it within 0.8(if $count = 0.1 - 0.7), it gives the
> > proper output. Why is it so?
>
> This is a FAQ. Have a look at:
>
> perldoc -q 999
>
> > Please let me know your suggestion.
>
> In a nutshell, some numbers cannot be exactly represented in binary, for
> the same reason that numbers such as one-third cannot be exactly represented
> in decimal.
>
> For this reason, it's best to avoid direct equality tests on floating-point
> numbers. For example, you could rewrite your test of $count to:
>
> if ($count >= 0.9) { ... }
>
> Another common technique is to measure the difference (aka delta) between a
> float and a known value, and consider them equal if the delta is small enough:
>
> if (abs(0.9 - $count) < 0.000001) { ... }
>
> For more (much more) detail, have a look at "What every computer scientist
> should know about floating-point arithmetic."
>
> <http://docs.sun.com/source/806-3568/ncg_goldberg.html>
>
> sherm--
>
> --
> WV News, Blogging, and Discussion:http://wv-www.com
> Cocoa programming in Perl:http://camelbones.sourceforge.net
Thanks Sherm..
------------------------------
Date: Mon, 12 Nov 2007 21:18:44 -0800
From: Nithy <nithyananthamm@yahoo.com>
Subject: Re: Reg- Floating point variables
Message-Id: <1194931124.887960.295700@s15g2000prm.googlegroups.com>
On Nov 12, 8:30 pm, "A. Sinan Unur" <1...@llenroc.ude.invalid> wrote:
> Nithy <nithyananth...@yahoo.com> wrote in news:1194876827.609769.271960
> @z24g2000prh.googlegroups.com:
>
> > #!/usr/bin/perl
> > #This program increments the value from x.1 to x.9
>
> for my $i ( 1 .. 9 ) {
> $x += $i/10;
>
> }
> > Why is it so?
>
> perldoc -q 999
>
> Sinan
>
> --
> A. Sinan Unur <1...@llenroc.ude.invalid>
> (remove .invalid and reverse each component for email address)
> clpmisc guidelines: <URL:http://www.augustmail.com/~tadmc/clpmisc.shtml>
Thanks Sinan..
------------------------------
Date: Mon, 12 Nov 2007 21:19:13 -0800
From: Nithy <nithyananthamm@yahoo.com>
Subject: Re: Reg- Floating point variables
Message-Id: <1194931153.402442.133360@k35g2000prh.googlegroups.com>
On Nov 12, 8:23 pm, "J=FCrgen Exner" <jurge...@hotmail.com> wrote:
> Nithy wrote:
> > If I run this code, it doesn't terminate when $count reach 0.9. Its
> > keep on increasing. And after 5.9 its showing 5.99999999999999 & so
> > on..
> > But If I limits it within 0.8(if $count =3D 0.1 - 0.7), it gives the
> > proper output. Why is it so?
>
> You must have missed "Basics of Computer Numerics":
> Thou shalt not test for equal on floating point numbers
>
> 'perldoc -q 999' gives a very brief introduction of why using floating po=
int
> numbers has it quirks in Perl, too, just like in any other standard
> programming language.
>
> jue
Thanks Jue..
------------------------------
Date: Mon, 12 Nov 2007 21:20:18 -0800
From: Nithy <nithyananthamm@yahoo.com>
Subject: Re: Reg- Floating point variables
Message-Id: <1194931218.243594.228660@e9g2000prf.googlegroups.com>
On Nov 12, 7:58 pm, smallpond <smallp...@juno.com> wrote:
> On Nov 12, 9:13 am, Nithy <nithyananth...@yahoo.com> wrote:
>
>
>
> > Hi,
> > Can anyone help me in floating point round off error. I have the
> > code as shown below.
>
> > #!/usr/bin/perl
> > #This program increments the value from x.1 to x.9
>
> > $count = 0;
> > $out = 0;
> > while($out == 0)
> > {
> > print ("count = ",$count,"\n");
> > $count=$count + 0.1;
> > if ($count == 0.9)
> > {
> > $out=1;
>
> > }
>
> > If I run this code, it doesn't terminate when $count reach 0.9. Its
> > keep on increasing. And after 5.9 its showing 5.99999999999999 & so
> > on..
> > But If I limits it within 0.8(if $count = 0.1 - 0.7), it gives the
> > proper output. Why is it so?
>
> > Please let me know your suggestion.
>
> > Thanks in advance.
>
> > Regards,
> > Nithy
>
> Never try to test for exactly equal to a floating point number.
> It doesn't work. Floating point numbers are approximate.
> Change your code to
> if ($count >= 0.9)
> --S
Thanks for your prompt response Smallpond.
------------------------------
Date: Tue, 13 Nov 2007 01:46:36 -0800
From: cieux87-fin@yahoo.com
Subject: replace string contaning \n
Message-Id: <1194947196.118603.155770@50g2000hsm.googlegroups.com>
hello.
I try to change the string \nE by # E without success.
$line=~ s/(\n\E/#E/g;
Thank you in advance for your assistance.
------------------------------
Date: Tue, 13 Nov 2007 02:13:36 -0800
From: sheinrich@my-deja.com
Subject: Re: replace string contaning \n
Message-Id: <1194948816.976763.76820@57g2000hsv.googlegroups.com>
On Nov 13, 10:46 am, cieux87-...@yahoo.com wrote:
> hello.
>
> I try to change the string \nE by # E without success.
>
> $line=~ s/(\n\E/#E/g;
>
> Thank you in advance for your assistance.
Is it the string constant '\nE' that you'd like to replace or do you
want to replace all line breaks by '#' which are being followed by
'E'?
And what does the '(' in your regex stand for?
In the first case
$line=~ s/\\nE/#E/g;
in the 2nd case
$line=~ s/\nE/#E/g;
Cheers,
Steffen
------------------------------
Date: Mon, 12 Nov 2007 19:01:25 -0800
From: "comp.llang.perl.moderated" <ced@blv-sam-01.ca.boeing.com>
Subject: Re: sleep/fork/shell/SIGCHLD interaction problem
Message-Id: <1194922885.338565.149640@k35g2000prh.googlegroups.com>
On Nov 11, 7:41 am, Justin Fletcher <ge...@gerph.org> wrote:
> Hiya,
>
> I'm having a problem trying to get a simple program to respond the way
> that I expect. The basic premise is thus :
>
> 1. Fork a child.
> 2. Sleep for a while.
> 3. Do other stuff.
>
> This seems pretty simple, and I have a SIGCHLD handler which will catch my
> forked process if it exits. I thought everything was fine. Then I found
> that is I press ctrl-Z to suspend the parent whilst I'm running the
> program and then background it, it hangs. I've reduced the problem to the
> simplest I can, as follows :
>
> ----
> #!/bin/perl
>
> $SIG{'CHLD'} = sub {
> print "SIGCHLD\n";
> $pid = wait;
> print "leave SIGCHLD for pid $pid\n";
> };
>
> print "Forking to do some long running task\n";
> unless ($pid = fork) {
> $SIG{'CHLD'} = 'DEFAULT';
> exec "tail -f /dev/null";
> die "failed\n";
> };
>
> print "Sleeping\n";
> sleep 50;
> print "Waking\n";
> ----
>
> The problem is that if I press ctrl-Z whilst the program is sleeping, and
> then resume it in the background with 'bg', a SIGCHLD is triggered. The
> handler then does a 'wait' to get the PID and hangs because there isn't a
> child that's exited. We never leave the SIGCHLD handler (unless the long
> running task completes). The use of 'tail -f /dev/null' is purely to
> simulate a task which just keeps running.
>
> In the shell, the following sequence is seen:
>
> ----
> justin@buttercup:~/Root/perltest$ perl testsleep.pl
> Forking to do some long running task
> Sleeping
>
> [1]+ Stopped perl testsleep.pl
> justin@buttercup:~/Root/perltest$ bg
> [1]+ perl testsleep.pl &
> SIGCHLD
> justin@buttercup:~/Root/perltest$
> ----
>
> I'm running bash 3.1.17, linux kernel 2.6.18, from debian stable, with
> perl 5.8.8.
>
> I believe this sort of construct to be normal and even recommended from
> the perlipc pages; so... am I doing something wrong ? is bash ? is the
> kernel ? is perl ?
>
think you could lose the SIGCHLD handler
as it's not necessary at all here. You're
not spawning multiple processes and SIGSTP
is problematic as you've seen. A simple
waitpid on the child should eliminate the
problems, eg.,
my $pid = fork;
die "fork: $!" unless defined $pid;
unless ($pid) { # child
exec "tail -f /dev/null"
or die "exec failed: $!\n";
} else { # parent
sleep 50;
waitpid $pid, 0;
}
--
Charles DeRykus
------------------------------
Date: 6 Apr 2001 21:33:47 GMT (Last modified)
From: Perl-Users-Request@ruby.oce.orst.edu (Perl-Users-Digest Admin)
Subject: Digest Administrivia (Last modified: 6 Apr 01)
Message-Id: <null>
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------------------------------
End of Perl-Users Digest V11 Issue 1028
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