Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

sed using wildcard

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting sed using wildcard
# 1  
Old 11-22-2012
sed using wildcard
Hi Folks,

I had a requirement to replace a pattern a.*a with 'a' alone. I'm writing a sed command to do that. But I'm not able to work this out. Pls help me.

Code:
echo 'a123a456a789' | sed 's/a.*a/a/'

Expected o/p : a456a789
But actual o/p is a789. Smilie

how can write that search pattern in sed to replace the first occurance alone.?

Thanks,
Poova.
Last edited by Scrutinizer; 11-25-2012 at 08:46 AM.. Reason: code tags
# 2  
Old 11-22-2012
Code:
echo 'a123a456a789' | sed 's/a[^a]*a/a/'

# 3  
Old 11-22-2012
And if that value is in a variable and you are using ksh93/bash (run shopt -s extglob in bash, first):
Code:
var=a123a456a789
echo ${var/a*([!a])a/a}
a456a789

# 4  
Old 11-25-2012
Any shell:
Code:
var=a123a456a789

echo "a${var#a*a}"

# 5  
Old 11-25-2012
With awk
Code:
echo 'a123a456a789' | awk '{ sub(/a[0-9]+a/,"a");print}'
a456a789

# 6  
Old 11-26-2012
Quote:
Originally Posted by Scrutinizer
Any shell:
Code:
var=a123a456a789

echo "a${var#a*a}"

That will work in any shell but will give undesired results if shortest match for the pattern a*a is not found in the variable value.
# 7  
Old 11-26-2012
Quote:
Originally Posted by Scrutinizer
Any shell:
Code:
var=a123a456a789

echo "a${var#a*a}"

This is true for any shell that supports the variable expansions specified by the POSIX standards and the Single UNIX Specifications for a variable that contains at least two "a" characters. The C shell (csh) and related shells usually do not support ${varOPpattern} expansions where OP is #, ##, %, or %%.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

sed replace characters using a wildcard

Hello, I have some data that looks like the following, > <SALTDATA> (OVS0199262) HCl > <IDNUMBER> (OVS0199262) OVS0199262 > <SUPPLIER> (OVS0199262) TimTec > <EMAIL> (OVS0199262) info@timtec.net > <WEBSITE> (OVS0199262) http://www.timtec.net I need to remove the data in... (3 Replies)
Discussion started by: LMHmedchem
3 Replies

2. Shell Programming and Scripting

Sed Wildcard

Hello, I apologize for asking what is probably a simple question but I have been unable to understand the other posts on the topic. I have a file that has the following several lines: ABC DEF GH:IJKLMNOP_QRS_TUV_11112012_ABCL5 ABC DEF GH:IJKLMNOP_QRS_TUV_11112013_ABCL4 ABC DEF... (4 Replies)
Discussion started by: MolecularToast
4 Replies

3. Shell Programming and Scripting

Wildcard use with SED command

Hello, I am fairly new to Linux in general and I am trying to use SED to make some replacements in a file. Below is sample of what the file is like. <Grouping id="024"><Source>ABC</Source><GroupingKey>000000000816</GroupingKey></Grouping><Grouping... (9 Replies)
Discussion started by: runforfun7
9 Replies

4. Shell Programming and Scripting

wildcard in sed substitution

I have a number of strings that I want to remove: <b>Task: 100</b> <b>Task: 1100 </b> <b>Task: 2200 </b> But the numbers in them can vary from 4, 5 8, digits in length. But, no alpha chars. I tried this: sed '/Task:/,//d' $file > tmpfile ; mv tmpfile $file But it removed additional text on... (5 Replies)
Discussion started by: dba_frog
5 Replies

5. Shell Programming and Scripting

sed delete wildcard within a string

Hi I would like to batch delete the "note" entry from bib files. The start would be defined by "note ={" and the end by "}." (see example bib entry below). I tried the following command which does not have any effect: cat input.bib| sed -e 's/note = {.*}.//' > output.bib Any help would... (2 Replies)
Discussion started by: gerggeismann
2 Replies

6. Shell Programming and Scripting

sed to delete lines from a file by using wildcard

I have a text file with tons of data and I want to remove all lines which are have "240" regardless of ABC or BCD and shouldnt delete anything else ABC_10_00024045.zip blah blah ABC_10_00024045.zip.new ABC_10_00024046.zip blah blah ABC_10_00024046.zip.new ABC_10_00024446.zip blah blah... (3 Replies)
Discussion started by: gubbu
3 Replies

7. Shell Programming and Scripting

use sed do batch wildcard string replace

Hi, Here is what I want to do I want to search local directory and its sub directory, all the files which contain any string like _12345, then remove this string. String is a combination of _ plus a random integer number. For example, here is one line in a file before <properties... (1 Reply)
Discussion started by: bp5000
1 Replies

8. Shell Programming and Scripting

how to cut string with wildcard (sed)

i got text file and contain.... SKYPE Dec 11 09:26:05 IN=eth0 OUT=eth1 SRC=75.38.161.80 DST=192.168.1.56 PROTO=UDP SPT=30645 DPT=12630 LEN=66 SKYPE Dec 11 09:26:05 IN=eth1 OUT=eth0 SRC=192.168.1.56 DST=118.109.39.86 PROTO=UDP SPT=12630 DPT=15889 LEN=75 SKYPE Dec 11 09:26:05 IN=eth1 OUT=eth0... (2 Replies)
Discussion started by: slackman
2 Replies

9. Shell Programming and Scripting

sed help/wildcard substitution

I need to perform the following substitutions and have been struggling to determine if or how I can do this with sed or perl. I need to change the string foo(bar) to moo(bar,0) wherever this occurs in a file. Is there a way to do this? I'm thinking there might be a wildcard of some sort that... (4 Replies)
Discussion started by: Mike@NZ
4 Replies

10. Shell Programming and Scripting

Single character wildcard for SED

Could someone tell me the single character wildcard for SED? I have the file below: $ more input2 AAA /A/B/C BBB /D/E/F CCC /G/H/I DDD I want to remove all strings which contain forward slashs "/" to get the below: AAA BBB CCC I tried to do it in SED by the command below but I... (8 Replies)
Discussion started by: stevefox
8 Replies
Login or Register to Ask a Question