Creating a regex expression


Login or Register for Dates, Times and to Reply

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Creating a regex expression
# 1  
Creating a regex expression

Good morning all!!

In my code I and looking through file /etc/syslog.congf and printing every line that has /var/log in it. I need to turn the if 9$line) into a regex code instead.

Code:
 #!/usr/bin/perl
 
  @file= 'cat /etc/syslog.conf';   //when 
 
  foreach $line (@file){
  if ($line =~ '/var/log'){
  print $line;
  }
  }

Thanks in advance for some help!! Would: if ($line =~ /?var*log?/) work?

Ben
# 2  
You need to match the line correctly (with literals and wildcards, etc). It seems you are only matching an optional '/' and then the literal string 'va' and then zero or more 'r' (greedy) and then the literal string 'lo' and then an optional 'g'.... which is not correct.

First of all, is '/var/log/*' always at the beginning of the line? What comes after?

It is always best to post the text in the file or variable you are trying to match so any member who wants to reply can test what they are doing against the text, not just incomplete fragments.
# 3  
Hi ,
Try this


if ($line =~ /\/var\/log/) { print $line ;}
# 4  
Pravin-thanks so much it works!! I had that earlier but then got confused with the /

Ben
Login or Register for Dates, Times and to Reply

Previous Thread | Next Thread
Thread Tools Search this Thread
Search this Thread:
Advanced Search

Test Your Knowledge in Computers #533
Difficulty: Easy
A Boolean is type of variable that is used to hold a truth value, either true or false.
True or False?

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

Sed: -e expression #1, char 20: unterminated address regex

I am trying to add word in last of particular line. the same command syntex is running on prompt. but in bash script give error."sed: -e expression #1, char 20: unterminated address regex" Please help. for i in `cat servername`; do ssh -q -t root@$i sed -i '/simple_allow_groups =/s/$/,... (4 Replies)
Discussion started by: yash_message
4 Replies

2. UNIX for Beginners Questions & Answers

Regex Expression Replace

I have a XML file where there is a tag with like <wd:address_line_1>1234 Street</wd:address_line_1> I want to replace the values "1234 Street" with "Test Data". Different people have different address lines and i want to replace with a fixed value to mask the file. I was trying to use sed... (7 Replies)
Discussion started by: dr46014
7 Replies

3. Shell Programming and Scripting

awk regex expression works in AIX but not in Linux

I have following expression: echo "Sun 12 Jul BST 2014\nSun 12 Jul 2014\nSun 12 Jul IS 2014" | awk '/(Sun)+( 12)+( Jul )+({3} )?(2014)/{print;}' I ran above code in AIX box and output is as follows Sun 12 Jul BST 2014 Sun 12 Jul 2014 I ran above code in Linux box and output is as... (8 Replies)
Discussion started by: kamlesh_pradhan
8 Replies

4. Shell Programming and Scripting

Hi im new to bash scripting I want to know what does the regex expression do ??

# check host value regex='^(||1|2|25)(\.(||1|2|25)){3}$' if ')" != "" ]; then if ]; then echo host $host not found exit 4 fi elif ]; then echo $host is an invalid host address exit 5 fi (1 Reply)
Discussion started by: kevin298
1 Replies

5. Emergency UNIX and Linux Support

Regular expression (regex) clean up text

Hi, Server - MEDIAWIKI - MYSQL - CENTOS 5 - PHP5 I have a database import of close to a million pages into my wiki, mediawiki site, the format that were left with is not pretty, and I need to find a way to clean this up and present it nicely... I think regex is the best option as I can... (1 Reply)
Discussion started by: lawstudent
1 Replies

6. Shell Programming and Scripting

awk variables in regex expression ?

Hello, Could someone explain why this one returns nothing: $ x=/jon/ $ echo jon | awk -v xa=$x '$1~xa {print}' $ while the following works fine: $ x=jon $ echo jon | awk -v xa=$x '$1==xa {print}' $ jon and the following works fine: $ echo jon | awk '$1~/jon/ {print}' $ jon ... (3 Replies)
Discussion started by: vilius
3 Replies

7. Shell Programming and Scripting

help with simple regex expression

I am trying to grep the following line in a file using a bash shell: (..) admin1::14959:::::: (..) It works with the following expression (as expected) # cat file | grep ^*:: admin1::14959:::::: but it does not work with (not expected) # cat /etc/shadow | grep ^+:: I assume the... (2 Replies)
Discussion started by: schms
2 Replies

8. UNIX for Advanced & Expert Users

Regular expression / regex substition on Unicode text

I have a large file encoded in Unicode that I need to convert to CSV. In general, I know how to do this by regular expression substitutions using sed or Perl, but one problem I am having is that I need to put a quotation mark at the end of each line to protect the last field. The usual regex... (1 Reply)
Discussion started by: thomas.hedden
1 Replies

9. Shell Programming and Scripting

Regular expression (regex) required

I want to block all special characters except alphanumerics.. and "."(dot ) character currently am using // I want to even block only single dot or multiple dots.. ex: . or .............. should be blocked. please provide me the reg ex. ---------- Post updated at 05:11 AM... (10 Replies)
Discussion started by: shams11
10 Replies

10. Shell Programming and Scripting

Replace if regex on specific column matches expression?

I am attempting to convert rewrite rules to Nginx, and since due to the mass amount of rewrites we must convert, I've been trying to write a script to help me on a specific part, easily. So far I have this: rewrite ^action/static/(+)/$ staticPage.php?pg=$1&%$query_string; What I want done... (5 Replies)
Discussion started by: EXT3FSCK
5 Replies

Featured Tech Videos