Sponsored Content
Full Discussion: Regex learning.
Top Forums Shell Programming and Scripting Regex learning. Post 303043992 by RavinderSingh13 on Wednesday 12th of February 2020 08:55:35 AM
Old 02-12-2020
Quote:
Originally Posted by nezabudka
Hi
It's a bit redundant
option -i applies to the whole template
Code:
grep -ioP 'project\D+\K(\d+\.([\d,a-z]+\.){1,}[\d,a-z]+|\d+\.[\d,a-z]+|\d+)'

if you want to limit it is better so
Code:
grep -oP '(?i:project)'

Hello Nez,

Cool; thanks for letting your views , but IMHO why I added that checks in case version is in some other format then it shouldn't have false positive in output.

Thanks,
R. Singh
This User Gave Thanks to RavinderSingh13 For This Post:
 

8 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

learning on my own

can i do this? i am learning this on my own..and from the book..simple unix i am not sure if the syntax would work if statement then statement do or for or while statement done else statement fi.... I dont know how else to explain that...I hope I... (2 Replies)
Discussion started by: jonas27
2 Replies

2. 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

3. Shell Programming and Scripting

Learning Perl

Folks! Anyone please explain the behavior of this program step by step. Thanks. #! /usr/bin/perl $testfile = "./testfile2"; for ( $i = 1, $i <= 5, $i++) { open ($FILE, ">", $testfile); print ($FILE "Output 1 \n"); close ($FILE); } print "The value of (4 * 2) / 2 is "; print (4 * 2)... (1 Reply)
Discussion started by: huko99
1 Replies

4. UNIX for Dummies Questions & Answers

Need advice on learning RegEx

Hello Unix graduates, I have gone through 50 posts here in this Unix.com, out of which 35-40 are answered with regex.. Regex is always been a problem for me. :wall: I have gone through few URLs still it doesn't help me to reach what you guys are.. :confused: How to get skilled on... (1 Reply)
Discussion started by: sathyaonnuix
1 Replies

5. UNIX for Dummies Questions & Answers

read regex from ID file, print regex and line below from source file

I have a file of protein sequences with headers (my source file). Based on a list of IDs (which are included in some of the headers), I'd like to print out only the specified sequences, with only the ID as header. In other words, I'd like to search source.txt for the terms in IDs.txt, and print... (3 Replies)
Discussion started by: pathunkathunk
3 Replies

6. Programming

Learning C with CBT?

Hello All, I am a beginner in C, although I believe my learning curve is rather steep. I would like to know if any of you would have some recommendations with some learning materials to become a good C developer. I am particularly thinking about some CBT courses or some good Quizz that would... (2 Replies)
Discussion started by: freddie50
2 Replies

7. 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

8. Shell Programming and Scripting

Sendmail K command regex: adding exclusion/negative lookahead to regex -a@MATCH

I'm trying to get some exclusions into our sendmail regular expression for the K command. The following configuration & regex works: LOCAL_CONFIG # Kcheckaddress regex -a@MATCH +<@+?\.++?\.(us|info|to|br|bid|cn|ru) LOCAL_RULESETS SLocal_check_mail # check address against various regex... (0 Replies)
Discussion started by: RobbieTheK
0 Replies
regex(1F)                                                          FMLI Commands                                                         regex(1F)

NAME
regex - match patterns against a string SYNOPSIS
regex [-e] [ -v "string"] [ pattern template] ... pattern [template] DESCRIPTION
The regex command takes a string from the standard input, and a list of pattern / template pairs, and runs regex() to compare the string against each pattern until there is a match. When a match occurs, regex writes the corresponding template to the standard output and returns TRUE. The last (or only) pattern does not need a template. If that is the pattern that matches the string, the function simply returns TRUE. If no match is found, regex returns FALSE. The argument pattern is a regular expression of the form described in regex(). In most cases, pattern should be enclosed in single quotes to turn off special meanings of characters. Note that only the final pattern in the list may lack a template. The argument template may contain the strings $m0 through $m9, which will be expanded to the part of pattern enclosed in ( ... )$0 through ( ... )$9 constructs (see examples below). Note that if you use this feature, you must be sure to enclose template in single quotes so that FMLI does not expand $m0 through $m9 at parse time. This feature gives regex much of the power of cut(1), paste(1), and grep(1), and some of the capabilities of sed(1). If there is no template, the default is $m0$m1$m2$m3$m4$m5$m6$m7$m8$m9. OPTIONS
The following options are supported: -e Evaluates the corresponding template and writes the result to the standard output. -v "string" Uses string instead of the standard input to match against patterns. EXAMPLES
Example 1: Cutting letters out of a string To cut the 4th through 8th letters out of a string (this example will output strin and return TRUE): `regex -v "my string is nice" '^.{3}(.{5})$0' '$m0'` Example 2: Validating input in a form In a form, to validate input to field 5 as an integer: valid=`regex -v "$F5" '^[0-9]+$'` Example 3: Translating an environment variable in a form In a form, to translate an environment variable which contains one of the numbers 1, 2, 3, 4, 5 to the letters a, b, c, d, e: value=`regex -v "$VAR1" 1 a 2 b 3 c 4 d 5 e '.*' 'Error'` Note the use of the pattern '.*' to mean "anything else". Example 4: Using backquoted expressions In the example below, all three lines constitute a single backquoted expression. This expression, by itself, could be put in a menu defini- tion file. Since backquoted expressions are expanded as they are parsed, and output from a backquoted expression (the cat command, in this example) becomes part of the definition file being parsed, this expression would read /etc/passwd and make a dynamic menu of all the login ids on the system. `cat /etc/passwd | regex '^([^:]*)$0.*$' ' name=$m0 action=`message "$m0 is a user"`'` DIAGNOSTICS
If none of the patterns match, regex returns FALSE, otherwise TRUE. NOTES
Patterns and templates must often be enclosed in single quotes to turn off the special meanings of characters. Especially if you use the $m0 through $m9 variables in the template, since FMLI will expand the variables (usually to "") before regex even sees them. Single characters in character classes (inside []) must be listed before character ranges, otherwise they will not be recognized. For exam- ple, [a-zA-Z_/] will not find underscores (_) or slashes (/), but [_/a-zA-Z] will. The regular expressions accepted by regcmp differ slightly from other utilities (that is, sed, grep, awk, ed, and so forth). regex with the -e option forces subsequent commands to be ignored. In other words, if a backquoted statement appears as follows: `regex -e ...; command1; command2` command1 and command2 would never be executed. However, dividing the expression into two: `regex -e ...``command1; command2` would yield the desired result. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
awk(1), cut(1), grep(1), paste(1), sed(1), regcmp(3C), attributes(5) SunOS 5.10 12 Jul 1999 regex(1F)

Featured Tech Videos

All times are GMT -4. The time now is 11:07 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy