07-24-2008
\1 is a backreference to what is matched in the parenthesis in the regexp. So /(.)\1/ finds a double occurance of whatever (.) matched. It is similar to $1 but is used inside the regexp. It is discussed in some detail here:
perlretut - perldoc.perl.org
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Hi,
Can anyone help me to find regular expression for the following in Perl?
"The string can only contain lower case letters (a-z) and no more than one of any letter."
For example: "table" is accepted, whether "dude" is not.
I have coded like this:
$str = "table";
if ($str =~ m/\b()\b/) {... (4 Replies)
Discussion started by: evilfreakz
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2. Shell Programming and Scripting
I have got numbers like
l255677
l376039
l188144
l340482
l440700
l254113
to match the numbers starting with '13' what would be the regex
=~/13(.*)/ =======>This is not working ....
But for user123,user657
regex =~/user(.*)/ ========>works
Thanks for help..!! (7 Replies)
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3. Shell Programming and Scripting
I am having trouble parsing rpm filenames in a shell script.. I found a snippet of perl code that will perform the task but I really don't have time to rewrite the entire script in perl. I cannot for the life of me convert this code into something sed-friendly:
if ($rpm =~ /(*)-(*)-(*)\.(.*)/)... (1 Reply)
Discussion started by: suntzu
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4. UNIX for Dummies Questions & Answers
Hi,
I get the following when I cat a file *.log
xxxxx
=====
dasdas gwdgsg fdsagfsag agsdfag
=====
random data
=====
My output should look like :
If the random data after the 2nd ==== is null then OK should be printed else
the random data should be printed.
How do I go about this... (5 Replies)
Discussion started by: manutd
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5. Programming
HI,
I'm new to perl and need simple regex for reading a file using my perl script.
The text file reads as -
filename=/pot/uio/current/myremificates.txt
certificates=/pot/uio/current/userdir/conf/user/gamma/settings/security/... (3 Replies)
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6. Programming
Hi Guys
I have the following regex
$OSRELEASE = $1 if ($output =~ /(Mac OS X (Server )?10.\d)/);
output is currently
Mac OS X 10.7.5
when the introduction of Mac 10.8 output changes to
OS X 10.8.2
they have dropped the Mac bit so i changed the regex to be (2 Replies)
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7. Programming
Hello,
I'm trying to get a quick help on regex since i'm not a regular programmer.
Below is the line i'm trying to apply my regex to..i want to use the regex in a for loop and this line will keep on changing.
subject=... (4 Replies)
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8. Shell Programming and Scripting
Could anyone please make me understand how the ?= works below ..
After executing this I am getting the same output.
$string="I love chocolate.";
$string =~ s/chocolate(?= ice)/vanilla/;
print "$string\n"; (2 Replies)
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9. Shell Programming and Scripting
I am not a big expert in regex and have just little understanding of that language.
Could you help me to understand the regular Perl expression:
^(?!if\b|else\b|while\b|)(?:+?\s+){1,6}(+\s*)\(*\) *?(?:^*;?+){0,10}\{
------
This is regex to select functions from a C/C++ source and defined in... (2 Replies)
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10. Shell Programming and Scripting
Experts -
I found a script on one of the servers that I work on and I need help understanding
one of the lines.
I know what the script does, but I'm having a hard time understanding the grouping.
Can someone help me with this?
Here's the script...
#!/usr/bin/perl
use strict;
use... (2 Replies)
Discussion started by: timj123
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LEARN ABOUT CENTOS
uri::url
URI::URL(3) User Contributed Perl Documentation URI::URL(3)
NAME
URI::URL - Uniform Resource Locators
SYNOPSIS
$u1 = URI::URL->new($str, $base);
$u2 = $u1->abs;
DESCRIPTION
This module is provided for backwards compatibility with modules that depend on the interface provided by the "URI::URL" class that used to
be distributed with the libwww-perl library.
The following differences exist compared to the "URI" class interface:
o The URI::URL module exports the url() function as an alternate constructor interface.
o The constructor takes an optional $base argument. The "URI::URL" class is a subclass of "URI::WithBase".
o The URI::URL->newlocal class method is the same as URI::file->new_abs.
o URI::URL::strict(1)
o $url->print_on method
o $url->crack method
o $url->full_path: same as ($uri->abs_path || "/")
o $url->netloc: same as $uri->authority
o $url->epath, $url->equery: same as $uri->path, $uri->query
o $url->path and $url->query pass unescaped strings.
o $url->path_components: same as $uri->path_segments (if you don't consider path segment parameters)
o $url->params and $url->eparams methods
o $url->base method. See URI::WithBase.
o $url->abs and $url->rel have an optional $base argument. See URI::WithBase.
o $url->frag: same as $uri->fragment
o $url->keywords: same as $uri->query_keywords
o $url->localpath and friends map to $uri->file.
o $url->address and $url->encoded822addr: same as $uri->to for mailto URI
o $url->groupart method for news URI
o $url->article: same as $uri->message
SEE ALSO
URI, URI::WithBase
COPYRIGHT
Copyright 1998-2000 Gisle Aas.
perl v5.16.3 2012-02-11 URI::URL(3)