Re: Edit a file inplace..

[James Edward Gray II]

On Jul 19, 2004, at 10:56 AM, [EMAIL PROTECTED] wrote:


Hi,
I am trying to edit an ASCII file in place…
I tried …
  perl -pi -ne "s/ERROR/TRACKED/g" status.log
Well, we definitely don't need -p and -n, since -p is -n plus some.
and received…
  Can't do inplace edit without backup…
Okay, let's try using a backup:
perl -pi.bak -e "s/ERROR/TRACKED/g" status.log
I believe Activestate Perl for Windows requires this.
Hope that helps.
James
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RE: Processing files in Multiple directories (Bash or Perl?)

[Moon, John]

Original Message-
From: Edward WIJAYA [mailto:[EMAIL PROTECTED] 
Sent: Monday, July 19, 2004 11:37 AM
To: [EMAIL PROTECTED]
Subject: Processing files in Multiple directories (Bash or Perl?)

Hi,

I have a perl code, with usage:

mycode.pl file.txt > file1.out

Now I would like to execute this code
for files in multiple directory (e.g. dir1, dir2, dir3, ...dir10).

As I am new for both Bash and Perl, would like to know
if it is be easier to do this with Perl or Bash?


I have already have a bash script (didn't know how to proceed):

---
#!bin/bash

for i in *
do
 if [ -d $i ]
 then
find $i -name '*.fa*'

#perl mycode.pl $i > #? don't know how to go from here
  fi
done
-

Would any body kindly advice?

Thanks so much for your time.
Hope to hear from you again

Regards
Edward WIJAYA
SINGAPORE


I find this easier to do but then I know perl better than bash...

DEV,SUN2>./foo file1=a,b,c/d/e file2=x/f/g file3=/,home/cgi-bin
Find file2 in Dirs = (x/f/g)
Find file1 in Dirs = (a,b,c/d/e)
Find file3 in Dirs = (/,home/cgi-bin)
DEV,SUN2>more foo
#! /usr/local/bin/perl
use strict;
my %params;
foreach (@ARGV) {
my ($file, $dirs)=split /=/;
@{$params{$file}} = split /,/, $dirs;
}
foreach (keys %params) {
print "Find $_ in Dirs = (", join (',', @{$params{$_}}), ')', "\n";
# do any "stuff" you want then call the already existing perl script
  # like see if the file exist in the dir before calling other
script 
  # or better yet - sub ... I develop lots of things in little
blocks
  # get them working then combine... 
}
DEV,SUN2>

I also like the way read "reads" ...

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perl.beginners Weekly list FAQ posting

[casey]

NAME
beginners-faq - FAQ for the beginners mailing list

1 -  Administriva
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  1.11 - When was this FAQ last updated?
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2 -  Questions about the 'beginners' list.
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  2.9 Other tips before posti

Processing files in Multiple directories (Bash or Perl?)

[Edward WIJAYA]

Hi,
I have a perl code, with usage:
mycode.pl file.txt > file1.out
Now I would like to execute this code
for files in multiple directory (e.g. dir1, dir2, dir3, ...dir10).
As I am new for both Bash and Perl, would like to know
if it is be easier to do this with Perl or Bash?
I have already have a bash script (didn't know how to proceed):
---
#!bin/bash
for i in *
do
if [ -d $i ]
then
   find $i -name '*.fa*'
#perl mycode.pl $i > #? don't know how to go from here
 fi
done
-
Would any body kindly advice?
Thanks so much for your time.
Hope to hear from you again
Regards
Edward WIJAYA
SINGAPORE
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Re: Another Perl datatype headache ( scalars $, hashes %, and arrays @ )

[James Edward Gray II]

On Jul 18, 2004, at 7:59 PM, gohaku wrote:
Hi everyone,
Howdy.
after writing perl scripts for about 3 years now, I still have trouble 
with the
basic datatypes.
I know that variables that start with '$' are scalars.
This covers Hashes ($HASH{$key}), Arrays ( $_[0] ), and
regular scalar values ( $foobar );
Looks like you are doing good to me.
The code I write as well other's code is still unreadable to me
even though I have followed examples from the
Camel book, many other Perl books from O'Reilly and online references.
I have also used perldoc on many occasions.
I'm sorry to hear that.  Sounds like you are doing most of the right 
things.  Perhaps you just need to give it some more time.

There are still some things that haven't sunk in, such as:
If I want to add Hash keys to another Hash, I do the following:
%HASH = ( 1 => 'one' ); #NO BRACES OR ELSE
%HASH2 = ( 2 => 'two' ); AGAIN, NO BRACES OR ELSE...
@HASH2{ keys %HASH } = "";
#confusing, considering it's the symbol used for arrays
If it's confusing, let's do it a different way.
for my $key (keys %HASH) {
$HASH{$key} = "";
}
Shorter isn't always better.  Use what you can understand.
To get the length of an array, it's $#array, not [EMAIL PROTECTED] or #$array.
Usually, I use scalar @array;
$#array is not the length of the array.  It is the number (#) of the 
last scalar ($) held in the array or more simply, the last index that 
has been assigned.

scalar(@array) is the length and the way to go, so again I see no 
problem here.

Problems with subroutines where the array is the first argument
sub badsub()
{  
 
my (@array,$scalar) = @_;   
#Pass Array last!
#my ($scalar,@array) = @_:
...
}
Again, you show the fix for the problem you mention.  Looks like you 
understand a lot more than you give yourself credit for.

If you are sure your sub is called:
some_sub( @array, $scalar )
You could use:
sub some_sub {
my $scalar = pop @_;
my @array = @_;
# ...
}
But I much prefer reversing the order, as you did above.
I still don't know how to declare arrays using only '$' instead of '@'
I believe you are talking about references here.  They would be a good 
solution to the problem above.  Using them you can pass 5 arrays, 3 
hashes and 2 scalars to a sub in any order you like.

However, they complicate things a little.  If you're still having 
trouble grasping Perl without them, give it a little more time before 
running down that road.

anyway, Is it possible to write scripts using only '$' instead of 
other prefix symbols?
In other words, a php-style script written in perl
Whether it is or not, it's not the answer to your problems.
Start trying to make sense of the world you find yourself in.  There 
are rules.  Try to understand why things are happening, not just that 
they are happening.

$ is for scalars.  Even with $hash{some_key} and $array[0] we're 
talking about one entry of the group, a scalar.

@ is for when we are talking about an array as a whole:
my @array  # create array
scalar @array  # get length of array
@array = @_  # copy array
% is similar, for the hash as a whole.  For example, we don't want the 
keys() of one entry of a hash, that doesn't make sense.  We want the 
keys() of an entire hash, so we call it with:

keys %some_hash
With sub routines, everything passed is folded into an array @_.  We do 
that so subroutines can handle varying numbers of parameters with ease. 
 Because of that, if we pass an array and a scalar, they are going to 
end up in @_ together and we need to separate them back out on the 
inside.  We've seen different ways to do that above, and references 
provide yet another way.

Hopefully some of this makes sense and helps get you over the hump.  
Hang in there.

James
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Re: Pattern Matching records from a table query.

[jason corbett]

Thanks James. I am going to try this method also. Your input is very much appreciated.
 
JC

James Edward Gray II <[EMAIL PROTECTED]> wrote:
On Jul 16, 2004, at 3:46 PM, jason corbett wrote:

> I want to eliminate the ". " (periord) or "," (comma) from records 
> that I return from a query, but I cannot figure out how to approach 
> it. Does Perl have a way that I can match a string that from an array, 
> remove a character or characters?
>
>
> For example say I have array @records that contain the following:
>
> Myrecord1 Myrecord2 Myrecord3 Myrecord4 Myrecord5, inc. 
> Myrecord6, LP Myrecord7, LLC
>
> I want to send this query out to persons in a .csv file but the 
> join(",", @record) statement that I am using causes the and extra cell 
> to be created at Myrecord5, inc. Myrecord6, LP Myrecord7, LLC.

How about?

tr/.,//d foreach @records;

James


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RE: Another Perl datatype headache ( scalars $, hashes %, and arr ays @ )

[Hanson, Rob]

> I still don't know how to declare arrays using only '$' instead of '@'

You can't.  But you can store a *reference* to an array in a scalar.

This will work:

# the backslash ("\") returns a reference to the
# variable, so this doesn't actually pass the array,
# it passes a reference (pointer sort of) to the array.
goodsub([EMAIL PROTECTED], $scalar);

sub goodsub()

{
  my ($array_ref,$scalar) = @_; 

  # turns the ref back to an actual array.
  my @array = @{$array_ref};

  # or use the array directly through the ref.
  # note that changes made through a ref will change
  # the original array.
  print $array_ref->[0];
}

> Is it possible to write scripts using only '$'
> instead of other prefix symbols?

No, not the way you intend.  You could use only references, but that
wouldn't make sense.

Rob

-Original Message-
From: gohaku [mailto:[EMAIL PROTECTED]
Sent: Sunday, July 18, 2004 8:59 PM
To: Perl Beginners
Subject: Another Perl datatype headache ( scalars $, hashes %, and
arrays @ )


Hi everyone,
after writing perl scripts for about 3 years now, I still have trouble 
with the
basic datatypes.
I know that variables that start with '$' are scalars.
This covers Hashes ($HASH{$key}), Arrays ( $_[0] ), and
regular scalar values ( $foobar );

The code I write as well other's code is still unreadable to me
even though I have followed examples from the
Camel book, many other Perl books from O'Reilly and online references.
I have also used perldoc on many occasions.

There are still some things that haven't sunk in, such as:

If I want to add Hash keys to another Hash, I do the following:

%HASH = ( 1 => 'one' ); #NO BRACES OR ELSE
%HASH2 = ( 2 => 'two' ); AGAIN, NO BRACES OR ELSE...
@HASH2{ keys %HASH } = "";
#confusing, considering it's the symbol used for arrays

To get the length of an array, it's $#array, not [EMAIL PROTECTED] or #$array.
Usually, I use scalar @array;

Problems with subroutines where the array is the first argument
sub badsub()

{

my (@array,$scalar) = @_;   
#Pass Array last!
#my ($scalar,@array) = @_:
...
}

I still don't know how to declare arrays using only '$' instead of '@'

anyway, Is it possible to write scripts using only '$' instead of other 
prefix symbols?
In other words, a php-style script written in perl

Thanks in advance.
-gohaku


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RE: Perl and XML::Simple

[Hanson, Rob]

> 

This isn't well-formed XML.  The n=3 must be n="3".  All attributes in XML
must be quoted, either single-quotes or double-quotes.

Rob

-Original Message-
From: David Arnold [mailto:[EMAIL PROTECTED]
Sent: Monday, July 19, 2004 2:04 AM
To: [EMAIL PROTECTED]
Subject: Perl and XML::Simple


All

I tried to run this:

#! /usr/local/bin/perl -w
# File: Responses.pl

use strict;
use warnings;

# Import the SML::Simple module
use XML::Simple;
use Data::Dumper;

# Turn the file into a has reference, using XML::Simples' "XMLin"
# subroutine. We'll also turn on the 'forcearray' option, so that all
# elements contain arrayrefs.
my $resp_xml=XMLin('./Responses.xml',forcearray=>1);

print Dumper $resp_xml;

On this file:

[EMAIL PROTECTED] perlxml]# cat -A Responses.xml
 aaa$
[EMAIL PROTECTED] perlxml]#

And I got this error message:

[EMAIL PROTECTED] perlxml]# ./Responses.pl
Not a quote character [Ln: 1, Col: 38]

Can anyone help?

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[This is what I needed]Pattern Matching records from a table query.

[jason corbett]

Thanks. I was using the Pipe thing, but the fact is my client wants it in Excel and to 
be able to open it immediately and not "click around with the parameters" as they are 
not Excel friendly (go figure). I appreaciate your willingness to carry the question 
out to a solution/example and not a quick fix!
 
JC

"Charles K. Clarkson" <[EMAIL PROTECTED]> wrote:
jason corbett wrote:

: I want to eliminate the ". " (periord) or "," (comma) from
: records that I return from a query, but I cannot figure out
: how to approach it. Does Perl have a way that I can match a
: string that from an array, remove a character or characters?
: 
: 
: For example say I have array @records that contain the
: following:
: 
: Myrecord1 Myrecord2 Myrecord3 Myrecord4
: Myrecord5, inc. Myrecord6, LP Myrecord7, LLC
: 
: I want to send this query out to persons in a .csv file but
: the join(",", @record) statement that I am using causes the
: and extra cell to be created at Myrecord5, inc. Myrecord6, LP
: Myrecord7, LLC. 
:
: What I am thinking is to scan records $record[4, 5, 6] by
: using regex matching, and if a comma exists, delete it or
: replace it with ";" . I am looking for some commands to do
: this, or at least point me in the right direction.
:
: Any suggestions?

You mention an extra cell. If you are using this for
import to a spreadsheet, you should be able to wrap suspect
fileds with double quotes. Try this.

$_ = qq("$_") foreach @record[4, 5, 6];
my $record_list = join ',', @record;


HTH,

Charles K. Clarkson
-- 
Mobile Homes Specialist
254 968-8328

problem while building DBD:Adabas

[Christian Stalp]

Hello out there,
I try to build a DBD:Adabas driver for DBI. And I got this dump:

# perl Makefile.PL

Configuring DBD::Adabas ...

>>> Remember to actually *READ* the README file!
And re-read it if you have any problems.

Multiple copies of Driver.xst found in: 
/usr/local/lib/perl5/5.8.3/PA-RISC2.0/auto/DBI 
/usr/local/lib/perl5/site_perl/5.8.3/PA-RISC2.0/auto/DBI at Makefile.PL line 
59
Using DBI 1.40 (for perl 5.008003 on PA-RISC2.0) installed in 
/usr/local/lib/perl5/5.8.3/PA-RISC2.0/auto/DBI
Using ODBC in /REFDB_HOME/referenz/adabas_d

Umm, this looks like a adabas type of driver manager.

Checking if your kit is complete...
Looks good
Multiple copies of Driver.xst found in: 
/usr/local/lib/perl5/5.8.3/PA-RISC2.0/auto/DBI 
/usr/local/lib/perl5/site_perl/5.8.3/PA-RISC2.0/auto/DBI at Makefile.PL line 
224
Using DBI 1.40 (for perl 5.008003 on PA-RISC2.0) installed in 
/usr/local/lib/perl5/5.8.3/PA-RISC2.0/auto/DBI
Writing Makefile for DBD::Adabas

The DBD::Adabas tests will use these values for the database connection:
DBI_DSN=dbi:Adabas:refdbe.g. dbi:Adabas:demo
DBI_USER=somewho
DBI_PASS=something


# make
cp Adabas.pm blib/lib/DBD/Adabas.pm
/usr/bin/perl -p -e "s/~DRIVER~/Adabas/g" 
/usr/local/lib/perl5/5.8.3/PA-RISC2.0/auto/DBI/Driver.xst > Adabas.xsi
/usr/bin/perl /usr/local/lib/perl5/5.8.3/ExtUtils/xsubpp  -typemap 
/usr/local/lib/perl5/5.8.3/ExtUtils/typemap  Adabas.xs > Adabas.xsc && mv 
Adabas.xsc Adabas.c
Warning: duplicate function definition 'data_sources' detected in Adabas.xs, 
line 114
/usr/local/bin/gcc -c  -I. 
-I/usr/local/lib/perl5/5.8.3/PA-RISC2.0/auto/DBI 
-I/REFDB_HOME/referenz/adabas_d/incl  -D_HPUX_SOURCE -fno-strict-aliasing 
-I/usr/local/include -D_LARGEFILE_SOURCE -O2-DVERSION=\"0.2003\"  
-DXS_VERSION=\"0.2003\" -fPIC "-I/usr/local/lib/perl5/5.8.3/PA-RISC2.0/CORE"  
 Adabas.c
In file included from dbdodbc.h:9,
 from Adabas.h:9,
 from Adabas.xs:1:
/REFDB_HOME/referenz/adabas_d/incl/WINDOWS.H:105:1: warning: "VOID" redefined
/REFDB_HOME/referenz/adabas_d/incl/WINDOWS.H:27:1: warning: this is the 
location of the previous definition
/usr/local/bin/gcc -c  -I. 
-I/usr/local/lib/perl5/5.8.3/PA-RISC2.0/auto/DBI 
-I/REFDB_HOME/referenz/adabas_d/incl  -D_HPUX_SOURCE -fno-strict-aliasing 
-I/usr/local/include -D_LARGEFILE_SOURCE -O2-DVERSION=\"0.2003\"  
-DXS_VERSION=\"0.2003\" -fPIC "-I/usr/local/lib/perl5/5.8.3/PA-RISC2.0/CORE"  
 dbdimp.c
In file included from dbdodbc.h:9,
 from Adabas.h:9,
 from dbdimp.c:12:
/REFDB_HOME/referenz/adabas_d/incl/WINDOWS.H:105:1: warning: "VOID" redefined
/REFDB_HOME/referenz/adabas_d/incl/WINDOWS.H:27:1: warning: this is the 
location of the previous definition
dbdimp.c: In function `adabas_db_login':
dbdimp.c:104: warning: passing arg 1 of `fprintf' from incompatible pointer 
typedbdimp.c: In function `adabas_error':
dbdimp.c:273: warning: passing arg 1 of `fprintf' from incompatible pointer 
typedbdimp.c:299: warning: passing arg 1 of `fprintf' from incompatible 
pointer typedbdimp.c:304: warning: passing arg 1 of `fprintf' from 
incompatible pointer typedbdimp.c:331: warning: passing arg 1 of `fprintf' 
from incompatible pointer typedbdimp.c: In function `dbd_preparse':
dbdimp.c:437: warning: passing arg 1 of `fprintf' from incompatible pointer 
typedbdimp.c: In function `dbd_st_tables':
dbdimp.c:489: warning: passing arg 1 of `fprintf' from incompatible pointer 
typedbdimp.c: In function `adabas_st_prepare':
dbdimp.c:560: warning: passing arg 1 of `fprintf' from incompatible pointer 
typedbdimp.c: In function `adabas_describe':
dbdimp.c:678: warning: passing arg 1 of `fprintf' from incompatible pointer 
typedbdimp.c:684: warning: passing arg 1 of `fprintf' from incompatible 
pointer typedbdimp.c:772: warning: passing arg 1 of `fprintf' from 
incompatible pointer typedbdimp.c:840: warning: passing arg 1 of `fprintf' 
from incompatible pointer typedbdimp.c: In function `adabas_st_execute':
dbdimp.c:871: warning: passing arg 1 of `fprintf' from incompatible pointer 
typedbdimp.c: In function `adabas_st_fetch':
dbdimp.c:951: warning: passing arg 1 of `fprintf' from incompatible pointer 
typedbdimp.c:976: warning: passing arg 1 of `fprintf' from incompatible 
pointer typedbdimp.c: In function `_dbd_rebind_ph':
dbdimp.c:1136: warning: passing arg 1 of `fprintf' from incompatible pointer 
type
dbdimp.c:1174: warning: passing arg 1 of `fprintf' from incompatible pointer 
type
dbdimp.c:1202: warning: passing arg 1 of `fprintf' from incompatible pointer 
type
dbdimp.c:1246: warning: passing arg 1 of `fprintf' from incompatible pointer 
type
dbdimp.c: In function `adabas_bind_ph':
dbdimp.c:1319: warning: passing arg 1 of `fprintf' from incompatible pointer 
type
dbdimp.c: In function `adabas_st_blob_read':
dbdimp.c:1398: warning: passing arg 1 of `fprintf' from incompatible pointer 
type
dbdimp.c:1424: warning: passi

Re: Another Perl datatype headache ( scalars $, hashes %, and arrays @ )

[Robin]

-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

On Mon, 19 Jul 2004 12:59, gohaku wrote:
> To get the length of an array, it's $#array, not [EMAIL PROTECTED] or #$array.
> Usually, I use scalar @array;
They do different things, afaik. $#array gives you the index of the last entry 
in the array, scalar @array gives you the size. So in general, 
[EMAIL PROTECTED]

> Problems with subroutines where the array is the first argument
> sub badsub()
> {
>   my (@array,$scalar) = @_;
>   #Pass Array last!
>   #my ($scalar,@array) = @_:
>   ...
> }
I got stuck for a while on this one. If you do this:
 my @a = (7,8,9);
 my $z = "hello";
 badsub(@a, $z);
it is turned into:
 badsub((7,8,9),"hello");
which, as Perl doesn't nest lists, and arguments are just lists, is:
 badsub(7,8,9,"hello");
you see why it gets messy now when you try to access it?

There are a few ways around it:
 badsub([EMAIL PROTECTED], $z);  # ugly, but sometimes useful if you have more than 
one list
 you want to keep apart
 badsub(@a, $z);   # where badsub has a prototype: ([EMAIL PROTECTED])
 badsub($z, @a);   # better still
I wrote a little bit about working with references here:
http://www.kallisti.net.nz/PerlTips/ReferencesPassedToSubroutines
when I got stuck. However, I've since learnt more that I need to add to that 
page. [Just done so]

> I still don't know how to declare arrays using only '$' instead of '@'
You can't, so far as I know. It doesn't make sense. @ signifies you want an 
array. $ signifies you want a scalar. Look at it this way: if you want a 
single value from something, prefix it with $. If you want a list, prefix it 
with @. If you provide a list when something is expecting a single item, it 
does 'scalar @list' which gives the size (someone correct me if I'm wrong 
here, please :)

> anyway, Is it possible to write scripts using only '$' instead of other
> prefix symbols?
> In other words, a php-style script written in perl
PHP works with them quite differently. In that, a variable starts with $ and 
may contain an array. It also doesn't have hashes like Perl (or rather, it 
doesn't have arrays like Perl, they are kind of like a mix of the two, 
similar to as if you didn't use arrays, but used hashs with '0', '1', '2' as 
the key). Note, my PHP knowledge isn't all that good, so I may not be totally 
accurate.

- -- 
Robin <[EMAIL PROTECTED]> JabberID: <[EMAIL PROTECTED]>

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