Sponsored Content
Top Forums Shell Programming and Scripting Looking for a perl-compatible regex solution Post 302896244 by spacebar on Saturday 5th of April 2014 09:38:16 PM
Old 04-05-2014
What will the actual record you want to scan look like?
 

9 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Perl REGEX

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
4 Replies

2. Shell Programming and Scripting

Perl script solution

Hi I need to do this thing in awk (or perl?). I try to find out how can I identify 1st and 2nd result from the OR expression in gensub: block='title Sata Mandriva kernel /boot/vmlinuz initrd /boot/initrd.img' echo "$block" | awk '{ x=gensub(/(kernel|initrd) /,"\\1XXX","g"); print x }' ... (12 Replies)
Discussion started by: webhope
12 Replies

3. Shell Programming and Scripting

Converting perl regex to sed regex

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
1 Replies

4. UNIX for Dummies Questions & Answers

Perl Regex Help!!!

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
5 Replies

5. Programming

Perl regex

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)
Discussion started by: ab52
2 Replies

6. Programming

Perl regex

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)
Discussion started by: jhamaks
4 Replies

7. Shell Programming and Scripting

?= in perl regex

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)
Discussion started by: scriptscript
2 Replies

8. Shell Programming and Scripting

Perl, RegEx - Help me to understand the regex!

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)
Discussion started by: alex_5161
2 Replies

9. Shell Programming and Scripting

Perl REGEX help

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
2 Replies
PREG_MATCH(3)								 1							     PREG_MATCH(3)

preg_match - Perform a regular expression match

SYNOPSIS
int preg_match (string $pattern, string $subject, [array &$matches], [int $flags], [int $offset]) DESCRIPTION
Searches $subject for a match to the regular expression given in $pattern. PARAMETERS
o $pattern - The pattern to search for, as a string. o $subject - The input string. o $matches - If $matches is provided, then it is filled with the results of search. $matches[0] will contain the text that matched the full pattern, $matches[1] will have the text that matched the first captured parenthesized subpattern, and so on. o $flags -$flags can be the following flag: o PREG_OFFSET_CAPTURE - If this flag is passed, for every occurring match the appendant string offset will also be returned. Note that this changes the value of $matches into an array where every element is an array consisting of the matched string at offset 0 and its string offset into $subject at offset 1. o $offset - Normally, the search starts from the beginning of the subject string. The optional parameter $offset can be used to specify the alternate place from which to start the search (in bytes). Note Using $offset is not equivalent to passing substr($subject, $offset) to preg_match(3) in place of the subject string, because $pattern can contain assertions such as ^, $ or (?<=x). Compare: <?php $subject = "abcdef"; $pattern = '/^def/'; preg_match($pattern, $subject, $matches, PREG_OFFSET_CAPTURE, 3); print_r($matches); ?> The above example will output: Array ( ) while this example <?php $subject = "abcdef"; $pattern = '/^def/'; preg_match($pattern, substr($subject,3), $matches, PREG_OFFSET_CAPTURE); print_r($matches); ?> will produce Array ( [0] => Array ( [0] => def [1] => 0 ) ) RETURN VALUES
preg_match(3) returns 1 if the $pattern matches given $subject, 0 if it does not, or FALSE if an error occurred. Warning This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE. Please read the section on Booleans for more information. Use the === operator for testing the return value of this function. CHANGELOG
+--------+---------------------------------------------------+ |Version | | | | | | | Description | | | | +--------+---------------------------------------------------+ | 5.3.6 | | | | | | | Returns FALSE if $offset is higher than $subject | | | length. | | | | | 5.2.2 | | | | | | | Named subpatterns now accept the syntax | | | (?<name>) and (?'name') as well as (?P<name>). | | | Previous versions accepted only (?P<name>). | | | | +--------+---------------------------------------------------+ EXAMPLES
Example #1 Find the string of text "php" <?php // The "i" after the pattern delimiter indicates a case-insensitive search if (preg_match("/php/i", "PHP is the web scripting language of choice.")) { echo "A match was found."; } else { echo "A match was not found."; } ?> Example #2 Find the word "web" <?php /* The  in the pattern indicates a word boundary, so only the distinct * word "web" is matched, and not a word partial like "webbing" or "cobweb" */ if (preg_match("/web/i", "PHP is the web scripting language of choice.")) { echo "A match was found."; } else { echo "A match was not found."; } if (preg_match("/web/i", "PHP is the website scripting language of choice.")) { echo "A match was found."; } else { echo "A match was not found."; } ?> Example #3 Getting the domain name out of a URL <?php // get host name from URL preg_match('@^(?:http://)?([^/]+)@i', "http://www.php.net/index.html", $matches); $host = $matches[1]; // get last two segments of host name preg_match('/[^.]+.[^.]+$/', $host, $matches); echo "domain name is: {$matches[0]} "; ?> The above example will output: domain name is: php.net Example #4 Using named subpattern <?php $str = 'foobar: 2008'; preg_match('/(?P<name>w+): (?P<digit>d+)/', $str, $matches); /* This also works in PHP 5.2.2 (PCRE 7.0) and later, however * the above form is recommended for backwards compatibility */ // preg_match('/(?<name>w+): (?<digit>d+)/', $str, $matches); print_r($matches); ?> The above example will output: Array ( [0] => foobar: 2008 [name] => foobar [1] => foobar [digit] => 2008 [2] => 2008 ) NOTES
Tip Do not use preg_match(3) if you only want to check if one string is contained in another string. Use strpos(3) or strstr(3) instead as they will be faster. SEE ALSO
PCRE Patterns, preg_quote(3), preg_match_all(3), preg_replace(3), preg_split(3), preg_last_error(3). PHP Documentation Group PREG_MATCH(3)
All times are GMT -4. The time now is 04:32 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy